78724905 has 16 divisors (see below), whose sum is σ = 143954304. Its totient is φ = 35988480.

The previous prime is 78724897. The next prime is 78724951. The reversal of 78724905 is 50942787.

It is not a de Polignac number, because 78724905 - 2³ = 78724897 is a prime.

It is a super-2 number, since 2×78724905² = 12395221334518050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 374776 + ... + 374985.

It is an arithmetic number, because the mean of its divisors is an integer number (8997144).

Almost surely, 2^78724905 is an apocalyptic number.

It is an amenable number.

78724905 is a deficient number, since it is larger than the sum of its proper divisors (65229399).

78724905 is a wasteful number, since it uses less digits than its factorization.

78724905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 749776.

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 78724905 is about 8872.7056189192. The cubic root of 78724905 is about 428.5854091471.

The spelling of 78724905 in words is "seventy-eight million, seven hundred twenty-four thousand, nine hundred five".