121687252569 has 9 divisors (see below), whose sum is σ = 175771987573. Its totient is φ = 81124137372.

The previous prime is 121687252501. The next prime is 121687252571. The reversal of 121687252569 is 965252786121.

The square root of 121687252569 is 348837.

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

121687252569 is a `hidden beast` number, since 1 + 2 + 1 + 6 + 8 + 72 + 5 + 2 + 569 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 121687252569 - 2²⁵ = 121653698137 is a prime.

It is a super-2 number, since 2×121687252569² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121687250569) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 988372 + ... + 1104650.

Almost surely, 2^121687252569 is an apocalyptic number.

121687252569 is the 348837-th square number.

121687252569 is the 174419-th centered octagonal number.

It is an amenable number.

121687252569 is a deficient number, since it is larger than the sum of its proper divisors (54084735004).

121687252569 is an frugal number, since it uses more digits than its factorization.

121687252569 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232564 (or 116282 counting only the distinct ones).

The product of its digits is 3628800, while the sum is 54.

The spelling of 121687252569 in words is "one hundred twenty-one billion, six hundred eighty-seven million, two hundred fifty-two thousand, five hundred sixty-nine".