51215369 has 2 divisors, whose sum is σ = 51215370. Its totient is φ = 51215368.

The previous prime is 51215357. The next prime is 51215377. The reversal of 51215369 is 96351215.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38291344 + 12924025 = 6188^2 + 3595^2 .

It is a cyclic number.

It is not a de Polignac number, because 51215369 - 2⁸ = 51215113 is a prime.

It is a super-2 number, since 2×51215369² = 5246028043612322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51215309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25607684 + 25607685.

It is an arithmetic number, because the mean of its divisors is an integer number (25607685).

Almost surely, 2^51215369 is an apocalyptic number.

It is an amenable number.

51215369 is a deficient number, since it is larger than the sum of its proper divisors (1).

51215369 is an equidigital number, since it uses as much as digits as its factorization.

51215369 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 51215369 is about 7156.4913889419. The cubic root of 51215369 is about 371.3642574401.

The spelling of 51215369 in words is "fifty-one million, two hundred fifteen thousand, three hundred sixty-nine".