249391920 has 80 divisors (see below), whose sum is σ = 774637920. Its totient is φ = 66373632.

The previous prime is 249391913. The next prime is 249391939. The reversal of 249391920 is 29193942.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×249391920² = 124392659522572800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 224326 + ... + 225434.

It is an arithmetic number, because the mean of its divisors is an integer number (9682974).

Almost surely, 2^249391920 is an apocalyptic number.

249391920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

249391920 is an abundant number, since it is smaller than the sum of its proper divisors (525246000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

249391920 is a wasteful number, since it uses less digits than its factorization.

249391920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2062 (or 2056 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 249391920 is about 15792.1474157253. The cubic root of 249391920 is about 629.4493550856.

The spelling of 249391920 in words is "two hundred forty-nine million, three hundred ninety-one thousand, nine hundred twenty".