43939690 has 8 divisors (see below), whose sum is σ = 79091460. Its totient is φ = 17575872.

The previous prime is 43939681. The next prime is 43939691. The reversal of 43939690 is 9693934.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 41589601 + 2350089 = 6449^2 + 1533^2 .

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

It is a super-2 number, since 2×43939690² = 3861392714592200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (43939691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2196975 + ... + 2196994.

Almost surely, 2^43939690 is an apocalyptic number.

43939690 is a deficient number, since it is larger than the sum of its proper divisors (35151770).

43939690 is a wasteful number, since it uses less digits than its factorization.

43939690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4393976.

The product of its (nonzero) digits is 157464, while the sum is 43.

The square root of 43939690 is about 6628.7019845517. The cubic root of 43939690 is about 352.8734603038.

The spelling of 43939690 in words is "forty-three million, nine hundred thirty-nine thousand, six hundred ninety".