231964781 has 8 divisors (see below), whose sum is σ = 235290744. Its totient is φ = 228659200.

The previous prime is 231964769. The next prime is 231964807. The reversal of 231964781 is 187469132.

231964781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 45778756 + 186186025 = 6766^2 + 13645^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 231964781 - 2¹⁸ = 231702637 is a prime.

It is a super-2 number, since 2×231964781² = 107615319248755922, 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 (231964741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18605 + ... + 28461.

It is an arithmetic number, because the mean of its divisors is an integer number (29411343).

Almost surely, 2^231964781 is an apocalyptic number.

It is an amenable number.

231964781 is a deficient number, since it is larger than the sum of its proper divisors (3325963).

231964781 is a wasteful number, since it uses less digits than its factorization.

231964781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10191.

The product of its digits is 72576, while the sum is 41.

The square root of 231964781 is about 15230.3900475333. The cubic root of 231964781 is about 614.4322704814.

The spelling of 231964781 in words is "two hundred thirty-one million, nine hundred sixty-four thousand, seven hundred eighty-one".