39990869 has 4 divisors (see below), whose sum is σ = 40403244. Its totient is φ = 39578496.

The previous prime is 39990857. The next prime is 39990911. The reversal of 39990869 is 96809993.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20295025 + 19695844 = 4505^2 + 4438^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39990869 is a prime.

It is a super-2 number, since 2×39990869² = 3198539206750322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 39990869.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39990829) 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, 206042 + ... + 206235.

It is an arithmetic number, because the mean of its divisors is an integer number (10100811).

Almost surely, 2^39990869 is an apocalyptic number.

It is an amenable number.

39990869 is a deficient number, since it is larger than the sum of its proper divisors (412375).

39990869 is an equidigital number, since it uses as much as digits as its factorization.

39990869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 412374.

The product of its (nonzero) digits is 944784, while the sum is 53.

The square root of 39990869 is about 6323.8334102030. The cubic root of 39990869 is about 341.9691643710.

The spelling of 39990869 in words is "thirty-nine million, nine hundred ninety thousand, eight hundred sixty-nine".