51478396969 has 2 divisors, whose sum is σ = 51478396970. Its totient is φ = 51478396968.

The previous prime is 51478396943. The next prime is 51478396993. The reversal of 51478396969 is 96969387415.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43227399744 + 8250997225 = 207912^2 + 90835^2 .

It is a cyclic number.

It is not a de Polignac number, because 51478396969 - 2²⁷ = 51344179241 is a prime.

It is a super-2 number, since 2×51478396969² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51478396069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25739198484 + 25739198485.

It is an arithmetic number, because the mean of its divisors is an integer number (25739198485).

Almost surely, 2^51478396969 is an apocalyptic number.

It is an amenable number.

51478396969 is a deficient number, since it is larger than the sum of its proper divisors (1).

51478396969 is an equidigital number, since it uses as much as digits as its factorization.

51478396969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 88179840, while the sum is 67.

The spelling of 51478396969 in words is "fifty-one billion, four hundred seventy-eight million, three hundred ninety-six thousand, nine hundred sixty-nine".