15249533121 has 15 divisors (see below), whose sum is σ = 22781827123. Its totient is φ = 10165614480.

The previous prime is 15249533119. The next prime is 15249533197. The reversal of 15249533121 is 12133594251.

It is a happy number.

The square root of 15249533121 is 123489.

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

15249533121 is a `hidden beast` number, since 1 + 524 + 9 + 5 + 3 + 3 + 121 = 666.

It can be written as a sum of positive squares in only one way, i.e., 3193493121 + 12056040000 = 56511^2 + 109800^2 .

It is not a de Polignac number, because 15249533121 - 2¹ = 15249533119 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (15249533521) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 1104541 + ... + 1118261.

Almost surely, 2^15249533121 is an apocalyptic number.

15249533121 is the 123489-th square number.

15249533121 is the 61745-th centered octagonal number.

It is an amenable number.

15249533121 is a deficient number, since it is larger than the sum of its proper divisors (7532294002).

15249533121 is an frugal number, since it uses more digits than its factorization.

15249533121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27454 (or 13724 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

Multiplying 15249533121 by its sum of digits (36), we get a square (548983192356 = 740934²).

Multiplying 15249533121 by its product of digits (32400), we get a square (494084873120400 = 22228020²).

The spelling of 15249533121 in words is "fifteen billion, two hundred forty-nine million, five hundred thirty-three thousand, one hundred twenty-one".