31421563 has 4 divisors (see below), whose sum is σ = 31437160. Its totient is φ = 31405968.

The previous prime is 31421561. The next prime is 31421581. The reversal of 31421563 is 36512413.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31421563 - 2¹ = 31421561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31421561) 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, 4233 + ... + 8986.

It is an arithmetic number, because the mean of its divisors is an integer number (7859290).

Almost surely, 2^31421563 is an apocalyptic number.

31421563 is a deficient number, since it is larger than the sum of its proper divisors (15597).

31421563 is a wasteful number, since it uses less digits than its factorization.

31421563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15596.

The product of its digits is 2160, while the sum is 25.

The square root of 31421563 is about 5605.4940014240. The cubic root of 31421563 is about 315.5556263959. Note that the first 3 decimals are identical.

Adding to 31421563 its reverse (36512413), we get a palindrome (67933976).

The spelling of 31421563 in words is "thirty-one million, four hundred twenty-one thousand, five hundred sixty-three".