253736640 has 168 divisors, whose sum is σ = 918880560. Its totient is φ = 64088064.

The previous prime is 253736629. The next prime is 253736663. The reversal of 253736640 is 46637352.

253736640 is a `hidden beast` number, since 2 + 5 + 3 + 7 + 3 + 6 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 253736595 and 253736604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52402 + ... + 57038.

Almost surely, 2^253736640 is an apocalyptic number.

253736640 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 253736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (459440280).

253736640 is an abundant number, since it is smaller than the sum of its proper divisors (665143920).

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

253736640 is a wasteful number, since it uses less digits than its factorization.

253736640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4679 (or 4666 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 36.

The square root of 253736640 is about 15929.1129696540. The cubic root of 253736640 is about 633.0835974436.

The spelling of 253736640 in words is "two hundred fifty-three million, seven hundred thirty-six thousand, six hundred forty".