15213495649 has 9 divisors (see below), whose sum is σ = 16723763539. Its totient is φ = 13829217160.

The previous prime is 15213495637. The next prime is 15213495667. The reversal of 15213495649 is 94659431251.

The square root of 15213495649 is 123343.

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

It can be written as a sum of positive squares in only one way, i.e., 604422225 + 14609073424 = 24585^2 + 120868^2 .

It is not a de Polignac number, because 15213495649 - 2¹¹ = 15213493601 is a prime.

It is a super-3 number, since 3×15213495649³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15213495749) 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, 1351167 + ... + 1362379.

Almost surely, 2^15213495649 is an apocalyptic number.

15213495649 is the 123343-rd square number.

15213495649 is the 61672-nd centered octagonal number.

It is an amenable number.

15213495649 is a deficient number, since it is larger than the sum of its proper divisors (1510267890).

15213495649 is an frugal number, since it uses more digits than its factorization.

15213495649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22448 (or 11224 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 49.

Multiplying 15213495649 by its sum of digits (49), we get a square (745461286801 = 863401²).

The spelling of 15213495649 in words is "fifteen billion, two hundred thirteen million, four hundred ninety-five thousand, six hundred forty-nine".