687130891 has 4 divisors (see below), whose sum is σ = 687192984. Its totient is φ = 687068800.

The previous prime is 687130879. The next prime is 687130897. The reversal of 687130891 is 198031786.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 687130891 - 2⁵ = 687130859 is a prime.

It is a super-2 number, since 2×687130891² = 944297722732907762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687130897) 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, 9430 + ... + 38251.

It is an arithmetic number, because the mean of its divisors is an integer number (171798246).

Almost surely, 2^687130891 is an apocalyptic number.

687130891 is a deficient number, since it is larger than the sum of its proper divisors (62093).

687130891 is a wasteful number, since it uses less digits than its factorization.

687130891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62092.

The product of its (nonzero) digits is 72576, while the sum is 43.

The square root of 687130891 is about 26213.1816268075. The cubic root of 687130891 is about 882.4291060599.

The spelling of 687130891 in words is "six hundred eighty-seven million, one hundred thirty thousand, eight hundred ninety-one".