20247531 has 4 divisors (see below), whose sum is σ = 26996712. Its totient is φ = 13498352.

The previous prime is 20247529. The next prime is 20247541. The reversal of 20247531 is 13574202.

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 20247531 - 2¹ = 20247529 is a prime.

It is a super-2 number, since 2×20247531² = 819925023191922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20247541) 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, 3374586 + ... + 3374591.

It is an arithmetic number, because the mean of its divisors is an integer number (6749178).

Almost surely, 2^20247531 is an apocalyptic number.

20247531 is a deficient number, since it is larger than the sum of its proper divisors (6749181).

20247531 is an equidigital number, since it uses as much as digits as its factorization.

20247531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6749180.

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 20247531 is about 4499.7256583041. The cubic root of 20247531 is about 272.5570107690.

The spelling of 20247531 in words is "twenty million, two hundred forty-seven thousand, five hundred thirty-one".