257121320 has 16 divisors (see below), whose sum is σ = 578523060. Its totient is φ = 102848512.

The previous prime is 257121313. The next prime is 257121323. The reversal of 257121320 is 23121752.

It is a happy number.

257121320 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 241926916 + 15194404 = 15554^2 + 3898^2 .

It is a super-2 number, since 2×257121320² = 132222746397084800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (257121323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3213977 + ... + 3214056.

Almost surely, 2^257121320 is an apocalyptic number.

257121320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257121320 is an abundant number, since it is smaller than the sum of its proper divisors (321401740).

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

257121320 is a wasteful number, since it uses less digits than its factorization.

257121320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6428044 (or 6428040 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 257121320 is about 16035.0029622698. The cubic root of 257121320 is about 635.8861457785.

The spelling of 257121320 in words is "two hundred fifty-seven million, one hundred twenty-one thousand, three hundred twenty".