78751257 has 16 divisors (see below), whose sum is σ = 119031360. Its totient is φ = 45911232.

The previous prime is 78751243. The next prime is 78751279. The reversal of 78751257 is 75215787.

It is not a de Polignac number, because 78751257 - 2⁶ = 78751193 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78751297) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52398 + ... + 53879.

It is an arithmetic number, because the mean of its divisors is an integer number (7439460).

Almost surely, 2^78751257 is an apocalyptic number.

It is an amenable number.

78751257 is a deficient number, since it is larger than the sum of its proper divisors (40280103).

78751257 is a wasteful number, since it uses less digits than its factorization.

78751257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106312.

The product of its digits is 137200, while the sum is 42.

The square root of 78751257 is about 8874.1904982934. The cubic root of 78751257 is about 428.6332246923.

The spelling of 78751257 in words is "seventy-eight million, seven hundred fifty-one thousand, two hundred fifty-seven".