20242731 has 4 divisors (see below), whose sum is σ = 26990312. Its totient is φ = 13495152.

The previous prime is 20242727. The next prime is 20242741. The reversal of 20242731 is 13724202.

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

It is not a de Polignac number, because 20242731 - 2² = 20242727 is a prime.

It is a super-2 number, since 2×20242731² = 819536316676722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20242698 and 20242707.

It is not an unprimeable number, because it can be changed into a prime (20242711) 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, 3373786 + ... + 3373791.

It is an arithmetic number, because the mean of its divisors is an integer number (6747578).

Almost surely, 2^20242731 is an apocalyptic number.

20242731 is a deficient number, since it is larger than the sum of its proper divisors (6747581).

20242731 is an equidigital number, since it uses as much as digits as its factorization.

20242731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6747580.

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 20242731 is about 4499.1922608397. The cubic root of 20242731 is about 272.5354710720.

Adding to 20242731 its reverse (13724202), we get a palindrome (33966933).

The spelling of 20242731 in words is "twenty million, two hundred forty-two thousand, seven hundred thirty-one".