87640831 has 8 divisors (see below), whose sum is σ = 93716784. Its totient is φ = 81667200.

The previous prime is 87640823. The next prime is 87640843. The reversal of 87640831 is 13804678.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 87640831 - 2³ = 87640823 is a prime.

It is a super-2 number, since 2×87640831² = 15361830516741122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87640031) 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 7 ways as a sum of consecutive naturals, for example, 23805 + ... + 27238.

It is an arithmetic number, because the mean of its divisors is an integer number (11714598).

Almost surely, 2^87640831 is an apocalyptic number.

87640831 is a deficient number, since it is larger than the sum of its proper divisors (6075953).

87640831 is a wasteful number, since it uses less digits than its factorization.

87640831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51161.

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 87640831 is about 9361.6681739955. The cubic root of 87640831 is about 444.1900530278.

The spelling of 87640831 in words is "eighty-seven million, six hundred forty thousand, eight hundred thirty-one".