78409623 has 16 divisors (see below), whose sum is σ = 108591840. Its totient is φ = 50282496.

The previous prime is 78409613. The next prime is 78409651. The reversal of 78409623 is 32690487.

It is not a de Polignac number, because 78409623 - 2⁴ = 78409607 is a prime.

It is a super-2 number, since 2×78409623² = 12296137958004258, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78409613) 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, 5911 + ... + 13847.

It is an arithmetic number, because the mean of its divisors is an integer number (6786990).

Almost surely, 2^78409623 is an apocalyptic number.

78409623 is a deficient number, since it is larger than the sum of its proper divisors (30182217).

78409623 is a wasteful number, since it uses less digits than its factorization.

78409623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8066.

The product of its (nonzero) digits is 72576, while the sum is 39.

The square root of 78409623 is about 8854.9208353322. The cubic root of 78409623 is about 428.0125025462.

The spelling of 78409623 in words is "seventy-eight million, four hundred nine thousand, six hundred twenty-three".