78130642 has 4 divisors (see below), whose sum is σ = 117195966. Its totient is φ = 39065320.

The previous prime is 78130631. The next prime is 78130667. The reversal of 78130642 is 24603187.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 44502241 + 33628401 = 6671^2 + 5799^2 .

It is a super-2 number, since 2×78130642² = 12208794438664328, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19532659 + ... + 19532662.

Almost surely, 2^78130642 is an apocalyptic number.

78130642 is a deficient number, since it is larger than the sum of its proper divisors (39065324).

78130642 is a wasteful number, since it uses less digits than its factorization.

78130642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39065323.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 78130642 is about 8839.1539187866. The cubic root of 78130642 is about 427.5042772847.

The spelling of 78130642 in words is "seventy-eight million, one hundred thirty thousand, six hundred forty-two".