38990818 has 4 divisors (see below), whose sum is σ = 58486230. Its totient is φ = 19495408.

The previous prime is 38990813. The next prime is 38990821. The reversal of 38990818 is 81809983.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81809983 = 421 ⋅194323.

It can be written as a sum of positive squares in only one way, i.e., 25573249 + 13417569 = 5057^2 + 3663^2 .

It is not an unprimeable number, because it can be changed into a prime (38990813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9747703 + ... + 9747706.

Almost surely, 2^38990818 is an apocalyptic number.

38990818 is a deficient number, since it is larger than the sum of its proper divisors (19495412).

38990818 is a wasteful number, since it uses less digits than its factorization.

38990818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19495411.

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 38990818 is about 6244.2628067691. The cubic root of 38990818 is about 339.0945284489.

The spelling of 38990818 in words is "thirty-eight million, nine hundred ninety thousand, eight hundred eighteen".