2661916205025 has 576 divisors, whose sum is σ = 6458922602496. Its totient is φ = 1053803520000.

The previous prime is 2661916205023. The next prime is 2661916205089. The reversal of 2661916205025 is 5205026191662.

2661916205025 is a `hidden beast` number, since 2 + 6 + 6 + 19 + 1 + 620 + 5 + 0 + 2 + 5 = 666.

It is not a de Polignac number, because 2661916205025 - 2¹ = 2661916205023 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2661916205023) by changing a digit.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 4314288517 + ... + 4314289133.

It is an arithmetic number, because the mean of its divisors is an integer number (11213407296).

Almost surely, 2^{2661916205025} is an apocalyptic number.

2661916205025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2661916205025 is an abundant number, since it is smaller than the sum of its proper divisors (3797006397471).

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

2661916205025 is a wasteful number, since it uses less digits than its factorization.

2661916205025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1084 (or 1067 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 2661916205025 in words is "two trillion, six hundred sixty-one billion, nine hundred sixteen million, two hundred five thousand, twenty-five".