23138731 has 12 divisors (see below), whose sum is σ = 29364120. Its totient is φ = 18029760.

The previous prime is 23138729. The next prime is 23138743. The reversal of 23138731 is 13783132.

It is not a de Polignac number, because 23138731 - 2¹ = 23138729 is a prime.

It is a super-2 number, since 2×23138731² = 1070801744580722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23138731.

It is not an unprimeable number, because it can be changed into a prime (23138701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20926 + ... + 22003.

It is an arithmetic number, because the mean of its divisors is an integer number (2447010).

Almost surely, 2^23138731 is an apocalyptic number.

23138731 is a deficient number, since it is larger than the sum of its proper divisors (6225389).

23138731 is a wasteful number, since it uses less digits than its factorization.

23138731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42954 (or 42947 counting only the distinct ones).

The product of its digits is 3024, while the sum is 28.

The square root of 23138731 is about 4810.2734849486. The cubic root of 23138731 is about 284.9573384384.

The spelling of 23138731 in words is "twenty-three million, one hundred thirty-eight thousand, seven hundred thirty-one".