23999981785 has 16 divisors (see below), whose sum is σ = 31600561104. Its totient is φ = 17388663552.

The previous prime is 23999981783. The next prime is 23999981807. The reversal of 23999981785 is 58718999932.

It can be written as a sum of positive squares in 8 ways, for example, as 1022272729 + 22977709056 = 31973^2 + 151584^2 .

It is not a de Polignac number, because 23999981785 - 2¹ = 23999981783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23999981783) 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, 3479862 + ... + 3486751.

It is an arithmetic number, because the mean of its divisors is an integer number (1975035069).

Almost surely, 2^23999981785 is an apocalyptic number.

It is an amenable number.

23999981785 is a deficient number, since it is larger than the sum of its proper divisors (7600579319).

23999981785 is a wasteful number, since it uses less digits than its factorization.

23999981785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6966684.

The product of its digits is 88179840, while the sum is 70.

The spelling of 23999981785 in words is "twenty-three billion, nine hundred ninety-nine million, nine hundred eighty-one thousand, seven hundred eighty-five".