64081919 has 8 divisors (see below), whose sum is σ = 70412160. Its totient is φ = 57835800.

The previous prime is 64081807. The next prime is 64081937. The reversal of 64081919 is 91918046.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64081919 - 2²⁰ = 63033343 is a prime.

It is a super-2 number, since 2×64081919² = 8212984685445122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64081019) 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, 19427 + ... + 22484.

It is an arithmetic number, because the mean of its divisors is an integer number (8801520).

Almost surely, 2^64081919 is an apocalyptic number.

64081919 is a deficient number, since it is larger than the sum of its proper divisors (6330241).

64081919 is a wasteful number, since it uses less digits than its factorization.

64081919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42061.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 64081919 is about 8005.1183001877. The cubic root of 64081919 is about 400.1705918191.

The spelling of 64081919 in words is "sixty-four million, eighty-one thousand, nine hundred nineteen".