257340617640 has 48 divisors (see below), whose sum is σ = 836357008500. Its totient is φ = 68624164608.

The previous prime is 257340617617. The next prime is 257340617641. The reversal of 257340617640 is 46716043752.

257340617640 is a `hidden beast` number, since 2 + 5 + 73 + 406 + 176 + 4 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 234339255396 + 23001362244 = 484086^2 + 151662^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (257340617641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 357417165 + ... + 357417884.

Almost surely, 2^257340617640 is an apocalyptic number.

257340617640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257340617640 is an abundant number, since it is smaller than the sum of its proper divisors (579016390860).

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

257340617640 is a wasteful number, since it uses less digits than its factorization.

257340617640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 714835066 (or 714835059 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 45.

The spelling of 257340617640 in words is "two hundred fifty-seven billion, three hundred forty million, six hundred seventeen thousand, six hundred forty".