23879781 has 18 divisors (see below), whose sum is σ = 36645362. Its totient is φ = 14981760.

The previous prime is 23879761. The next prime is 23879809. The reversal of 23879781 is 18797832.

It can be written as a sum of positive squares in 3 ways, for example, as 11390625 + 12489156 = 3375^2 + 3534^2 .

It is not a de Polignac number, because 23879781 - 2¹⁵ = 23847013 is a prime.

It is a super-2 number, since 2×23879781² = 1140487881215922, 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 (23879701) 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 17 ways as a sum of consecutive naturals, for example, 1990 + ... + 7191.

Almost surely, 2^23879781 is an apocalyptic number.

It is an amenable number.

23879781 is a deficient number, since it is larger than the sum of its proper divisors (12765581).

23879781 is a wasteful number, since it uses less digits than its factorization.

23879781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9221 (or 9201 counting only the distinct ones).

The product of its digits is 169344, while the sum is 45.

The square root of 23879781 is about 4886.6942814136. The cubic root of 23879781 is about 287.9674804138.

It can be divided in two parts, 2 and 3879781, that added together give a palindrome (3879783).

The spelling of 23879781 in words is "twenty-three million, eight hundred seventy-nine thousand, seven hundred eighty-one".