257420641 has 2 divisors, whose sum is σ = 257420642. Its totient is φ = 257420640.

The previous prime is 257420593. The next prime is 257420677. The reversal of 257420641 is 146024752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151413025 + 106007616 = 12305^2 + 10296^2 .

It is a cyclic number.

It is not a de Polignac number, because 257420641 - 2²¹ = 255323489 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (257420041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128710320 + 128710321.

It is an arithmetic number, because the mean of its divisors is an integer number (128710321).

Almost surely, 2^257420641 is an apocalyptic number.

It is an amenable number.

257420641 is a deficient number, since it is larger than the sum of its proper divisors (1).

257420641 is an equidigital number, since it uses as much as digits as its factorization.

257420641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13440, while the sum is 31.

The square root of 257420641 is about 16044.3336103436. Note that the first 3 decimals coincide. The cubic root of 257420641 is about 636.1328001170.

The spelling of 257420641 in words is "two hundred fifty-seven million, four hundred twenty thousand, six hundred forty-one".