78421216 has 12 divisors (see below), whose sum is σ = 154391832. Its totient is φ = 39210592.

The previous prime is 78421181. The next prime is 78421229. The reversal of 78421216 is 61212487.

It is a super-2 number, since 2×78421216² = 12299774237837312, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1225300 + ... + 1225363.

It is an arithmetic number, because the mean of its divisors is an integer number (12865986).

Almost surely, 2^78421216 is an apocalyptic number.

It is an amenable number.

78421216 is a deficient number, since it is larger than the sum of its proper divisors (75970616).

78421216 is a wasteful number, since it uses less digits than its factorization.

78421216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2450673 (or 2450665 counting only the distinct ones).

The product of its digits is 5376, while the sum is 31.

The square root of 78421216 is about 8855.5754189098. The cubic root of 78421216 is about 428.0335956393.

The spelling of 78421216 in words is "seventy-eight million, four hundred twenty-one thousand, two hundred sixteen".