31494987 has 16 divisors (see below), whose sum is σ = 47238560. Its totient is φ = 20995200.

The previous prime is 31494979. The next prime is 31495003. The reversal of 31494987 is 78949413.

It is not a de Polignac number, because 31494987 - 2³ = 31494979 is a prime.

It is a super-2 number, since 2×31494987² = 1983868412260338, 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 (31494907) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5014 + ... + 9387.

It is an arithmetic number, because the mean of its divisors is an integer number (2952410).

Almost surely, 2^31494987 is an apocalyptic number.

31494987 is a deficient number, since it is larger than the sum of its proper divisors (15743573).

31494987 is an frugal number, since it uses more digits than its factorization.

31494987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14422 (or 14404 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 31494987 is about 5612.0394688562. The cubic root of 31494987 is about 315.8012256021.

The spelling of 31494987 in words is "thirty-one million, four hundred ninety-four thousand, nine hundred eighty-seven".