78259957 has 4 divisors (see below), whose sum is σ = 80080000. Its totient is φ = 76439916.

The previous prime is 78259897. The next prime is 78259981. The reversal of 78259957 is 75995287.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78259957 - 2⁷ = 78259829 is a prime.

It is a super-2 number, since 2×78259957² = 12249241739283698, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78259997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 909957 + ... + 910042.

It is an arithmetic number, because the mean of its divisors is an integer number (20020000).

Almost surely, 2^78259957 is an apocalyptic number.

It is an amenable number.

78259957 is a deficient number, since it is larger than the sum of its proper divisors (1820043).

78259957 is a wasteful number, since it uses less digits than its factorization.

78259957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1820042.

The product of its digits is 1587600, while the sum is 52.

The square root of 78259957 is about 8846.4657914898. The cubic root of 78259957 is about 427.7400031686.

The spelling of 78259957 in words is "seventy-eight million, two hundred fifty-nine thousand, nine hundred fifty-seven".