64778394 has 16 divisors (see below), whose sum is σ = 129817440. Its totient is φ = 21549360.

The previous prime is 64778369. The next prime is 64778407. The reversal of 64778394 is 49387746.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7552 + ... + 13659.

It is an arithmetic number, because the mean of its divisors is an integer number (8113590).

Almost surely, 2^64778394 is an apocalyptic number.

64778394 is an abundant number, since it is smaller than the sum of its proper divisors (65039046).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64778394 is a wasteful number, since it uses less digits than its factorization.

64778394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21725.

The product of its digits is 1016064, while the sum is 48.

The square root of 64778394 is about 8048.5025936506. The cubic root of 64778394 is about 401.6151238266.

The spelling of 64778394 in words is "sixty-four million, seven hundred seventy-eight thousand, three hundred ninety-four".