251422420 has 12 divisors (see below), whose sum is σ = 527987124. Its totient is φ = 100568960.

The previous prime is 251422403. The next prime is 251422441. The reversal of 251422420 is 24224152.

It can be written as a sum of positive squares in 2 ways, for example, as 197458704 + 53963716 = 14052^2 + 7346^2 .

It is a junction number, because it is equal to n+sod(n) for n = 251422391 and 251422400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6285541 + ... + 6285580.

It is an arithmetic number, because the mean of its divisors is an integer number (43998927).

Almost surely, 2^251422420 is an apocalyptic number.

251422420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251422420 is an abundant number, since it is smaller than the sum of its proper divisors (276564704).

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

251422420 is a wasteful number, since it uses less digits than its factorization.

251422420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12571130 (or 12571128 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 251422420 is about 15856.3053704197. The cubic root of 251422420 is about 631.1530240859.

Adding to 251422420 its reverse (24224152), we get a palindrome (275646572).

The spelling of 251422420 in words is "two hundred fifty-one million, four hundred twenty-two thousand, four hundred twenty".