253645820 has 72 divisors (see below), whose sum is σ = 575623440. Its totient is φ = 93883104.

The previous prime is 253645807. The next prime is 253645837. The reversal of 253645820 is 28546352.

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, 5898719 + ... + 5898761.

It is an arithmetic number, because the mean of its divisors is an integer number (7994770).

Almost surely, 2^253645820 is an apocalyptic number.

253645820 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 253645820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287811720).

253645820 is an abundant number, since it is smaller than the sum of its proper divisors (321977620).

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

253645820 is an equidigital number, since it uses as much as digits as its factorization.

253645820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The square root of 253645820 is about 15926.2619594178. The cubic root of 253645820 is about 633.0080551889.

The spelling of 253645820 in words is "two hundred fifty-three million, six hundred forty-five thousand, eight hundred twenty".