64190778 has 16 divisors (see below), whose sum is σ = 135138720. Its totient is φ = 20270736.

The previous prime is 64190743. The next prime is 64190779. The reversal of 64190778 is 87709146.

It is not an unprimeable number, because it can be changed into a prime (64190779) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281425 + ... + 281652.

It is an arithmetic number, because the mean of its divisors is an integer number (8446170).

Almost surely, 2^64190778 is an apocalyptic number.

64190778 is an abundant number, since it is smaller than the sum of its proper divisors (70947942).

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

64190778 is a wasteful number, since it uses less digits than its factorization.

64190778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 563101.

The product of its (nonzero) digits is 84672, while the sum is 42.

The square root of 64190778 is about 8011.9147524172. The cubic root of 64190778 is about 400.3970598949.

It can be divided in two parts, 641 and 90778, that added together give a palindrome (91419).

The spelling of 64190778 in words is "sixty-four million, one hundred ninety thousand, seven hundred seventy-eight".