22423781 has 16 divisors (see below), whose sum is σ = 24931200. Its totient is φ = 20110464.

The previous prime is 22423759. The next prime is 22423787. The reversal of 22423781 is 18732422.

22423781 = 599² + 600² + ... + 655².

It is a de Polignac number, because none of the positive numbers 2^k-22423781 is a prime.

It is a super-2 number, since 2×22423781² = 1005651908671922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22423787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 231125 + ... + 231221.

It is an arithmetic number, because the mean of its divisors is an integer number (1558200).

Almost surely, 2^22423781 is an apocalyptic number.

It is an amenable number.

22423781 is a deficient number, since it is larger than the sum of its proper divisors (2507419).

22423781 is an frugal number, since it uses more digits than its factorization.

22423781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 139 counting only the distinct ones).

The product of its digits is 5376, while the sum is 29.

The square root of 22423781 is about 4735.3754866959. The cubic root of 22423781 is about 281.9916710314.

The spelling of 22423781 in words is "twenty-two million, four hundred twenty-three thousand, seven hundred eighty-one".