264640440 has 64 divisors (see below), whose sum is σ = 796262400. Its totient is φ = 70362752.

The previous prime is 264640433. The next prime is 264640471. The reversal of 264640440 is 44046462.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 264640398 and 264640407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40009 + ... + 46151.

It is an arithmetic number, because the mean of its divisors is an integer number (12441600).

Almost surely, 2^264640440 is an apocalyptic number.

264640440 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 264640440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (398131200).

264640440 is an abundant number, since it is smaller than the sum of its proper divisors (531621960).

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

264640440 is a wasteful number, since it uses less digits than its factorization.

264640440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6516 (or 6512 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 30.

The square root of 264640440 is about 16267.7730498062. The cubic root of 264640440 is about 642.0251928663.

The spelling of 264640440 in words is "two hundred sixty-four million, six hundred forty thousand, four hundred forty".