78917290 has 16 divisors (see below), whose sum is σ = 144172512. Its totient is φ = 31095504.

The previous prime is 78917269. The next prime is 78917303. The reversal of 78917290 is 9271987.

It is a happy number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 58224 + ... + 59563.

It is an arithmetic number, because the mean of its divisors is an integer number (9010782).

Almost surely, 2^78917290 is an apocalyptic number.

78917290 is a deficient number, since it is larger than the sum of its proper divisors (65255222).

78917290 is a wasteful number, since it uses less digits than its factorization.

78917290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117861.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 78917290 is about 8883.5403978369. The cubic root of 78917290 is about 428.9342455137.

The spelling of 78917290 in words is "seventy-eight million, nine hundred seventeen thousand, two hundred ninety".