231648640 has 64 divisors (see below), whose sum is σ = 577899360. Its totient is φ = 88625152.

The previous prime is 231648587. The next prime is 231648649. The reversal of 231648640 is 46846132.

231648640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×231648640² = 107322184827699200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231648596 and 231648605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231648649) 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, 6852 + ... + 22588.

Almost surely, 2^231648640 is an apocalyptic number.

231648640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231648640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (288949680).

231648640 is an abundant number, since it is smaller than the sum of its proper divisors (346250720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

231648640 is a wasteful number, since it uses less digits than its factorization.

231648640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15779 (or 15767 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 231648640 is about 15220.0078843606. The cubic root of 231648640 is about 614.1530103513.

The spelling of 231648640 in words is "two hundred thirty-one million, six hundred forty-eight thousand, six hundred forty".