265648498921 has 27 divisors (see below), whose sum is σ = 295147196613. Its totient is φ = 238985772480.

The previous prime is 265648498849. The next prime is 265648498961. The reversal of 265648498921 is 129894846562.

The square root of 265648498921 is 515411.

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

It can be written as a sum of positive squares in 4 ways, for example, as 176942216025 + 88706282896 = 420645^2 + 297836^2 .

It is not a de Polignac number, because 265648498921 - 2²³ = 265640110313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (265648498961) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 274713580 + ... + 274714546.

Almost surely, 2^265648498921 is an apocalyptic number.

265648498921 is the 515411-st square number.

265648498921 is the 257706-th centered octagonal number.

It is an amenable number.

265648498921 is a deficient number, since it is larger than the sum of its proper divisors (29498697692).

265648498921 is an frugal number, since it uses more digits than its factorization.

265648498921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2042 (or 1021 counting only the distinct ones).

The product of its digits is 59719680, while the sum is 64.

Multiplying 265648498921 by its sum of digits (64), we get a square (17001503930944 = 4123288²).

The spelling of 265648498921 in words is "two hundred sixty-five billion, six hundred forty-eight million, four hundred ninety-eight thousand, nine hundred twenty-one".