687870857961 has 64 divisors (see below), whose sum is σ = 1217948774400. Its totient is φ = 375155307648.

The previous prime is 687870857929. The next prime is 687870857963. The reversal of 687870857961 is 169758078786.

It is not a de Polignac number, because 687870857961 - 2⁵ = 687870857929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 687870857961.

It is not an unprimeable number, because it can be changed into a prime (687870857963) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1813450 + ... + 2159708.

It is an arithmetic number, because the mean of its divisors is an integer number (19030449600).

Almost surely, 2^687870857961 is an apocalyptic number.

It is an amenable number.

687870857961 is a deficient number, since it is larger than the sum of its proper divisors (530077916439).

687870857961 is a wasteful number, since it uses less digits than its factorization.

687870857961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 346755 (or 346749 counting only the distinct ones).

The product of its (nonzero) digits is 284497920, while the sum is 72.

The spelling of 687870857961 in words is "six hundred eighty-seven billion, eight hundred seventy million, eight hundred fifty-seven thousand, nine hundred sixty-one".