23397781 has 4 divisors (see below), whose sum is σ = 25524864. Its totient is φ = 21270700.

The previous prime is 23397769. The next prime is 23397791. The reversal of 23397781 is 18779332.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 23397781 - 2⁵ = 23397749 is a prime.

It is a super-2 number, since 2×23397781² = 1094912311447922, 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 (23397791) 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 3 ways as a sum of consecutive naturals, for example, 1063525 + ... + 1063546.

It is an arithmetic number, because the mean of its divisors is an integer number (6381216).

Almost surely, 2^23397781 is an apocalyptic number.

It is an amenable number.

23397781 is a deficient number, since it is larger than the sum of its proper divisors (2127083).

23397781 is a wasteful number, since it uses less digits than its factorization.

23397781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2127082.

The product of its digits is 63504, while the sum is 40.

The square root of 23397781 is about 4837.1252826446. The cubic root of 23397781 is about 286.0168091250.

The spelling of 23397781 in words is "twenty-three million, three hundred ninety-seven thousand, seven hundred eighty-one".