31453987 has 4 divisors (see below), whose sum is σ = 33109480. Its totient is φ = 29798496.

The previous prime is 31453969. The next prime is 31453991. The reversal of 31453987 is 78935413.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78935413 = 1231 ⋅64123.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31453987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31453957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 827718 + ... + 827755.

It is an arithmetic number, because the mean of its divisors is an integer number (8277370).

Almost surely, 2^31453987 is an apocalyptic number.

31453987 is a deficient number, since it is larger than the sum of its proper divisors (1655493).

31453987 is a wasteful number, since it uses less digits than its factorization.

31453987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1655492.

The product of its digits is 90720, while the sum is 40.

The square root of 31453987 is about 5608.3854182822. The cubic root of 31453987 is about 315.6641299981.

The spelling of 31453987 in words is "thirty-one million, four hundred fifty-three thousand, nine hundred eighty-seven".