78751257251 has 2 divisors, whose sum is σ = 78751257252. Its totient is φ = 78751257250.

The previous prime is 78751257107. The next prime is 78751257259. The reversal of 78751257251 is 15275215787.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78751257251 is a prime.

It is a super-2 number, since 2×78751257251² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78751257251.

It is not a weakly prime, because it can be changed into another prime (78751257259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39375628625 + 39375628626.

It is an arithmetic number, because the mean of its divisors is an integer number (39375628626).

Almost surely, 2^78751257251 is an apocalyptic number.

78751257251 is a deficient number, since it is larger than the sum of its proper divisors (1).

78751257251 is an equidigital number, since it uses as much as digits as its factorization.

78751257251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1372000, while the sum is 50.

The spelling of 78751257251 in words is "seventy-eight billion, seven hundred fifty-one million, two hundred fifty-seven thousand, two hundred fifty-one".