251820045 has 48 divisors (see below), whose sum is σ = 444487680. Its totient is φ = 131870592.

The previous prime is 251820043. The next prime is 251820047. The reversal of 251820045 is 540028152.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (251820043) and next prime (251820047).

It is not a de Polignac number, because 251820045 - 2¹ = 251820043 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251820043) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 794227 + ... + 794543.

It is an arithmetic number, because the mean of its divisors is an integer number (9260160).

Almost surely, 2^251820045 is an apocalyptic number.

It is an amenable number.

251820045 is a deficient number, since it is larger than the sum of its proper divisors (192667635).

251820045 is a wasteful number, since it uses less digits than its factorization.

251820045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 594 (or 591 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 251820045 is about 15868.8388043990. The cubic root of 251820045 is about 631.4855720455.

Adding to 251820045 its reverse (540028152), we get a palindrome (791848197).

The spelling of 251820045 in words is "two hundred fifty-one million, eight hundred twenty thousand, forty-five".