51125639 has 2 divisors, whose sum is σ = 51125640. Its totient is φ = 51125638.

The previous prime is 51125629. The next prime is 51125671. The reversal of 51125639 is 93652115.

It is an a-pointer prime, because the next prime (51125671) can be obtained adding 51125639 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51125639 - 2⁸ = 51125383 is a prime.

It is a super-2 number, since 2×51125639² = 5227661926316642, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51125629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25562819 + 25562820.

It is an arithmetic number, because the mean of its divisors is an integer number (25562820).

Almost surely, 2^51125639 is an apocalyptic number.

51125639 is a deficient number, since it is larger than the sum of its proper divisors (1).

51125639 is an equidigital number, since it uses as much as digits as its factorization.

51125639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8100, while the sum is 32.

The square root of 51125639 is about 7150.2195071200. The cubic root of 51125639 is about 371.1472523046.

The spelling of 51125639 in words is "fifty-one million, one hundred twenty-five thousand, six hundred thirty-nine".