249805642464 has 432 divisors, whose sum is σ = 857552346000. Its totient is φ = 70537775616.

The previous prime is 249805642441. The next prime is 249805642483. The reversal of 249805642464 is 464246508942.

249805642464 is a `hidden beast` number, since 2 + 4 + 98 + 0 + 56 + 42 + 464 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 249805642464.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1255304637 + ... + 1255304835.

It is an arithmetic number, because the mean of its divisors is an integer number (1985074875).

Almost surely, 2^249805642464 is an apocalyptic number.

249805642464 is a gapful number since it is divisible by the number (24) 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 249805642464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (428776173000).

249805642464 is an abundant number, since it is smaller than the sum of its proper divisors (607746703536).

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

249805642464 is a wasteful number, since it uses less digits than its factorization.

249805642464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 13271040, while the sum is 54.

The spelling of 249805642464 in words is "two hundred forty-nine billion, eight hundred five million, six hundred forty-two thousand, four hundred sixty-four".