681492187 has 8 divisors (see below), whose sum is σ = 689794560. Its totient is φ = 673222440.

The previous prime is 681492173. The next prime is 681492191. The reversal of 681492187 is 781294186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-681492187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681495187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35262 + ... + 51052.

It is an arithmetic number, because the mean of its divisors is an integer number (86224320).

Almost surely, 2^681492187 is an apocalyptic number.

681492187 is a deficient number, since it is larger than the sum of its proper divisors (8302373).

681492187 is a wasteful number, since it uses less digits than its factorization.

681492187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16313.

The product of its digits is 193536, while the sum is 46.

The square root of 681492187 is about 26105.4053215038. The cubic root of 681492187 is about 880.0086892221.

The spelling of 681492187 in words is "six hundred eighty-one million, four hundred ninety-two thousand, one hundred eighty-seven".