31987007 has 4 divisors (see below), whose sum is σ = 34447560. Its totient is φ = 29526456.

The previous prime is 31987001. The next prime is 31987019. The reversal of 31987007 is 70078913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70078913 = 17 ⋅4122289.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31987007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31987001) 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, 1230257 + ... + 1230282.

It is an arithmetic number, because the mean of its divisors is an integer number (8611890).

Almost surely, 2^31987007 is an apocalyptic number.

31987007 is a deficient number, since it is larger than the sum of its proper divisors (2460553).

31987007 is a wasteful number, since it uses less digits than its factorization.

31987007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2460552.

The product of its (nonzero) digits is 10584, while the sum is 35.

The square root of 31987007 is about 5655.7057030931. The cubic root of 31987007 is about 317.4372356145.

The spelling of 31987007 in words is "thirty-one million, nine hundred eighty-seven thousand, seven".