251122420 has 12 divisors (see below), whose sum is σ = 527357124. Its totient is φ = 100448960.

The previous prime is 251122387. The next prime is 251122423. The reversal of 251122420 is 24221152.

It can be written as a sum of positive squares in 2 ways, for example, as 151880976 + 99241444 = 12324^2 + 9962^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251122423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6278041 + ... + 6278080.

It is an arithmetic number, because the mean of its divisors is an integer number (43946427).

Almost surely, 2^251122420 is an apocalyptic number.

251122420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251122420 is an abundant number, since it is smaller than the sum of its proper divisors (276234704).

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

251122420 is a wasteful number, since it uses less digits than its factorization.

251122420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12556130 (or 12556128 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 251122420 is about 15846.8425877207. The cubic root of 251122420 is about 630.9018912619.

Adding to 251122420 its reverse (24221152), we get a palindrome (275343572).

The spelling of 251122420 in words is "two hundred fifty-one million, one hundred twenty-two thousand, four hundred twenty".