251420550 has 96 divisors (see below), whose sum is σ = 648842400. Its totient is φ = 64373760.

The previous prime is 251420539. The next prime is 251420563. The reversal of 251420550 is 55024152.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 251420550.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 493696 + ... + 494204.

It is an arithmetic number, because the mean of its divisors is an integer number (6758775).

Almost surely, 2^251420550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 251420550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324421200).

251420550 is an abundant number, since it is smaller than the sum of its proper divisors (397421850).

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

251420550 is a wasteful number, since it uses less digits than its factorization.

251420550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 650 (or 645 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 251420550 is about 15856.2464032318. The cubic root of 251420550 is about 631.1514593102.

The spelling of 251420550 in words is "two hundred fifty-one million, four hundred twenty thousand, five hundred fifty".