78042637 has 4 divisors (see below), whose sum is σ = 78129216. Its totient is φ = 77956060.

The previous prime is 78042623. The next prime is 78042647. The reversal of 78042637 is 73624087.

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, and also an emirpimes, since its reverse is a distinct semiprime: 73624087 = 3209 ⋅22943.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78042637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78042596 and 78042605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78042617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41923 + ... + 43744.

It is an arithmetic number, because the mean of its divisors is an integer number (19532304).

Almost surely, 2^78042637 is an apocalyptic number.

It is an amenable number.

78042637 is a deficient number, since it is larger than the sum of its proper divisors (86579).

78042637 is an equidigital number, since it uses as much as digits as its factorization.

78042637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86578.

The product of its (nonzero) digits is 56448, while the sum is 37.

The square root of 78042637 is about 8834.1743813443. The cubic root of 78042637 is about 427.3437058470.

The spelling of 78042637 in words is "seventy-eight million, forty-two thousand, six hundred thirty-seven".