251538049 has 4 divisors (see below), whose sum is σ = 287472064. Its totient is φ = 215604036.

The previous prime is 251538043. The next prime is 251538149. The reversal of 251538049 is 940835152.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 251538049 - 2⁷ = 251537921 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 251537999 and 251538017.

It is not an unprimeable number, because it can be changed into a prime (251538043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17966997 + ... + 17967010.

It is an arithmetic number, because the mean of its divisors is an integer number (71868016).

Almost surely, 2^251538049 is an apocalyptic number.

It is an amenable number.

251538049 is a deficient number, since it is larger than the sum of its proper divisors (35934015).

251538049 is an equidigital number, since it uses as much as digits as its factorization.

251538049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35934014.

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 251538049 is about 15859.9511033294. The cubic root of 251538049 is about 631.2497648726.

The spelling of 251538049 in words is "two hundred fifty-one million, five hundred thirty-eight thousand, forty-nine".