249721525 has 12 divisors (see below), whose sum is σ = 312398532. Its totient is φ = 198007040.

The previous prime is 249721513. The next prime is 249721573. The reversal of 249721525 is 525127942.

It can be written as a sum of positive squares in 6 ways, for example, as 76983076 + 172738449 = 8774^2 + 13143^2 .

It is not a de Polignac number, because 249721525 - 2⁷ = 249721397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41374 + ... + 47023.

It is an arithmetic number, because the mean of its divisors is an integer number (26033211).

Almost surely, 2^249721525 is an apocalyptic number.

249721525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

249721525 is a deficient number, since it is larger than the sum of its proper divisors (62677007).

249721525 is a wasteful number, since it uses less digits than its factorization.

249721525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88520 (or 88515 counting only the distinct ones).

The product of its digits is 50400, while the sum is 37.

The square root of 249721525 is about 15802.5796944676. The cubic root of 249721525 is about 629.7265337021.

The spelling of 249721525 in words is "two hundred forty-nine million, seven hundred twenty-one thousand, five hundred twenty-five".