51247969 has 2 divisors, whose sum is σ = 51247970. Its totient is φ = 51247968.

The previous prime is 51247961. The next prime is 51247981. The reversal of 51247969 is 96974215.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35247969 + 16000000 = 5937^2 + 4000^2 .

It is a cyclic number.

It is not a de Polignac number, because 51247969 - 2³ = 51247961 is a prime.

It is a super-2 number, since 2×51247969² = 5252708653249922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51247961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25623984 + 25623985.

It is an arithmetic number, because the mean of its divisors is an integer number (25623985).

Almost surely, 2^51247969 is an apocalyptic number.

It is an amenable number.

51247969 is a deficient number, since it is larger than the sum of its proper divisors (1).

51247969 is an equidigital number, since it uses as much as digits as its factorization.

51247969 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136080, while the sum is 43.

The square root of 51247969 is about 7158.7686790397. The cubic root of 51247969 is about 371.4430352708.

The spelling of 51247969 in words is "fifty-one million, two hundred forty-seven thousand, nine hundred sixty-nine".