249051905640 has 192 divisors, whose sum is σ = 835922280960. Its totient is φ = 64241210880.

The previous prime is 249051905633. The next prime is 249051905657. The reversal of 249051905640 is 46509150942.

249051905640 is a `hidden beast` number, since 2 + 4 + 90 + 519 + 0 + 5 + 6 + 40 = 666.

249051905640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 32996347 + ... + 33003893.

It is an arithmetic number, because the mean of its divisors is an integer number (4353761880).

Almost surely, 2^249051905640 is an apocalyptic number.

249051905640 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 249051905640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (417961140480).

249051905640 is an abundant number, since it is smaller than the sum of its proper divisors (586870375320).

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

249051905640 is a wasteful number, since it uses less digits than its factorization.

249051905640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10552 (or 10545 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 249051905640 in words is "two hundred forty-nine billion, fifty-one million, nine hundred five thousand, six hundred forty".