257145320 has 32 divisors (see below), whose sum is σ = 598530600. Its totient is φ = 99310848.

The previous prime is 257145311. The next prime is 257145353. The reversal of 257145320 is 23541752.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 201583204 + 55562116 = 14198^2 + 7454^2 .

It is a super-2 number, since 2×257145320² = 132247431195804800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109679 + ... + 111998.

Almost surely, 2^257145320 is an apocalyptic number.

257145320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257145320 is an abundant number, since it is smaller than the sum of its proper divisors (341385280).

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

257145320 is a wasteful number, since it uses less digits than its factorization.

257145320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221717 (or 221713 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 29.

The square root of 257145320 is about 16035.7513076251. The cubic root of 257145320 is about 635.9059299446.

The spelling of 257145320 in words is "two hundred fifty-seven million, one hundred forty-five thousand, three hundred twenty".