3987531 has 6 divisors (see below), whose sum is σ = 5759780. Its totient is φ = 2658348.

The previous prime is 3987523. The next prime is 3987551. The reversal of 3987531 is 1357893.

It is not a de Polignac number, because 3987531 - 2³ = 3987523 is a prime.

It is a super-2 number, since 2×3987531² = 31800806951922, which contains 22 as substring.

It is a Duffinian number.

3987531 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (3987521) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 221521 + ... + 221538.

Almost surely, 2^3987531 is an apocalyptic number.

3987531 is a deficient number, since it is larger than the sum of its proper divisors (1772249).

3987531 is a wasteful number, since it uses less digits than its factorization.

3987531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443065 (or 443062 counting only the distinct ones).

The product of its digits is 22680, while the sum is 36.

The square root of 3987531 is about 1996.8803168943. The cubic root of 3987531 is about 158.5749893110.

The spelling of 3987531 in words is "three million, nine hundred eighty-seven thousand, five hundred thirty-one".