1233678925521 has 81 divisors (see below), whose sum is σ = 2091062661051. Its totient is φ = 698841589824.

The previous prime is 1233678925499. The next prime is 1233678925601. The reversal of 1233678925521 is 1255298763321.

The square root of 1233678925521 is 1110711.

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

1233678925521 is a `hidden beast` number, since 1 + 2 + 3 + 3 + 6 + 7 + 89 + 2 + 552 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 250535286225 + 983143639296 = 500535^2 + 991536^2 .

It is not a de Polignac number, because 1233678925521 - 2⁵ = 1233678925489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1233678925321) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 5294759221 + ... + 5294759453.

Almost surely, 2^{1233678925521} is an apocalyptic number.

1233678925521 is the 1110711-st square number.

1233678925521 is the 555356-th centered octagonal number.

It is an amenable number.

1233678925521 is a deficient number, since it is larger than the sum of its proper divisors (857383735530).

1233678925521 is an frugal number, since it uses more digits than its factorization.

1233678925521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 940 (or 470 counting only the distinct ones).

The product of its digits is 5443200, while the sum is 54.

The spelling of 1233678925521 in words is "one trillion, two hundred thirty-three billion, six hundred seventy-eight million, nine hundred twenty-five thousand, five hundred twenty-one".