43921690 has 8 divisors (see below), whose sum is σ = 79059060. Its totient is φ = 17568672.

The previous prime is 43921687. The next prime is 43921723. The reversal of 43921690 is 9612934.

It can be written as a sum of positive squares in 2 ways, for example, as 41822089 + 2099601 = 6467^2 + 1449^2 .

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

It is a super-2 number, since 2×43921690² = 3858229704912200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2196075 + ... + 2196094.

Almost surely, 2^43921690 is an apocalyptic number.

43921690 is a deficient number, since it is larger than the sum of its proper divisors (35137370).

43921690 is a wasteful number, since it uses less digits than its factorization.

43921690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4392176.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 43921690 is about 6627.3441135948. The cubic root of 43921690 is about 352.8252685679.

The spelling of 43921690 in words is "forty-three million, nine hundred twenty-one thousand, six hundred ninety".