257906246781 has 16 divisors (see below), whose sum is σ = 365202969408. Its totient is φ = 161334624000.

The previous prime is 257906246777. The next prime is 257906246837. The reversal of 257906246781 is 187642609752.

It is a happy number.

It is not a de Polignac number, because 257906246781 - 2² = 257906246777 is a prime.

It is a super-2 number, since 2×257906246781² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257906246281) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 7622070 + ... + 7655831.

It is an arithmetic number, because the mean of its divisors is an integer number (22825185588).

Almost surely, 2^257906246781 is an apocalyptic number.

It is an amenable number.

257906246781 is a deficient number, since it is larger than the sum of its proper divisors (107296722627).

257906246781 is a wasteful number, since it uses less digits than its factorization.

257906246781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15278252.

The product of its (nonzero) digits is 10160640, while the sum is 57.

The spelling of 257906246781 in words is "two hundred fifty-seven billion, nine hundred six million, two hundred forty-six thousand, seven hundred eighty-one".