15639253249 has 9 divisors (see below), whose sum is σ = 15849736833. Its totient is φ = 15431533572.

The previous prime is 15639253211. The next prime is 15639253307. The reversal of 15639253249 is 94235293651.

It is a happy number.

The square root of 15639253249 is 125057.

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

It is not a de Polignac number, because 15639253249 - 2²¹ = 15637156097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15639253349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9878712 + ... + 9880294.

Almost surely, 2^15639253249 is an apocalyptic number.

15639253249 is the 125057-th square number.

15639253249 is the 62529-th centered octagonal number.

It is an amenable number.

15639253249 is a deficient number, since it is larger than the sum of its proper divisors (210483584).

15639253249 is an frugal number, since it uses more digits than its factorization.

15639253249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3324 (or 1662 counting only the distinct ones).

The product of its digits is 1749600, while the sum is 49.

Multiplying 15639253249 by its sum of digits (49), we get a square (766323409201 = 875399²).

The spelling of 15639253249 in words is "fifteen billion, six hundred thirty-nine million, two hundred fifty-three thousand, two hundred forty-nine".