999998001335025 has 1215 divisors, whose sum is σ = 2437451304595515. Its totient is φ = 390705339024000.

The previous prime is 999998001335023. The next prime is 999998001335027. The reversal of 999998001335025 is 520533100899999.

The square root of 999998001335025 is 31622745.

It is a perfect power (a square), and thus also a powerful number.

999998001335025 is a `hidden beast` number, since 9 + 9 + 9 + 9 + 9 + 80 + 0 + 1 + 33 + 502 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (999998001335023) and next prime (999998001335027).

It can be written as a sum of positive squares in only one way, i.e., 359999280480609 + 639998720854416 = 18973647^2 + 25298196^2 .

It is not a de Polignac number, because 999998001335025 - 2¹ = 999998001335023 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (999998001335023) by changing a digit.

It is a polite number, since it can be written in 1214 ways as a sum of consecutive naturals, for example, 7633572529210 + ... + 7633572529340.

Almost surely, 2^{999998001335025} is an apocalyptic number.

999998001335025 is a gapful number since it is divisible by the number (95) formed by its first and last digit.

999998001335025 is the 31622745-th square number.

999998001335025 is the 15811373-rd centered octagonal number.

It is an amenable number.

999998001335025 is an abundant number, since it is smaller than the sum of its proper divisors (1437453303260490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999998001335025 is a wasteful number, since it uses less digits than its factorization.

999998001335025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 212576400, while the sum is 72.

The spelling of 999998001335025 in words is "nine hundred ninety-nine trillion, nine hundred ninety-eight billion, one million, three hundred thirty-five thousand, twenty-five".