87724631 has 4 divisors (see below), whose sum is σ = 87743712. Its totient is φ = 87705552.

The previous prime is 87724627. The next prime is 87724639. The reversal of 87724631 is 13642778.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13642778 = 2 ⋅6821389.

It is a cyclic number.

It is not a de Polignac number, because 87724631 - 2² = 87724627 is a prime.

It is a super-2 number, since 2×87724631² = 15391221768172322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87724639) 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, 2051 + ... + 13403.

It is an arithmetic number, because the mean of its divisors is an integer number (21935928).

Almost surely, 2^87724631 is an apocalyptic number.

87724631 is a deficient number, since it is larger than the sum of its proper divisors (19081).

87724631 is a wasteful number, since it uses less digits than its factorization.

87724631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19080.

The product of its digits is 56448, while the sum is 38.

The square root of 87724631 is about 9366.1428026696. The cubic root of 87724631 is about 444.3315824511.

The spelling of 87724631 in words is "eighty-seven million, seven hundred twenty-four thousand, six hundred thirty-one".