39938987 has 4 divisors (see below), whose sum is σ = 43569816. Its totient is φ = 36308160.

The previous prime is 39938981. The next prime is 39938993. The reversal of 39938987 is 78983993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78983993 = 11 ⋅7180363.

It is an interprime number because it is at equal distance from previous prime (39938981) and next prime (39938993).

It is a cyclic number.

It is not a de Polignac number, because 39938987 - 2⁶ = 39938923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39938981) 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, 1815398 + ... + 1815419.

It is an arithmetic number, because the mean of its divisors is an integer number (10892454).

Almost surely, 2^39938987 is an apocalyptic number.

39938987 is a deficient number, since it is larger than the sum of its proper divisors (3630829).

39938987 is a wasteful number, since it uses less digits than its factorization.

39938987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3630828.

The product of its digits is 2939328, while the sum is 56.

The square root of 39938987 is about 6319.7299784089. The cubic root of 39938987 is about 341.8212162461.

The spelling of 39938987 in words is "thirty-nine million, nine hundred thirty-eight thousand, nine hundred eighty-seven".