16620389 has 4 divisors (see below), whose sum is σ = 16781856. Its totient is φ = 16458924.

The previous prime is 16620361. The next prime is 16620391. The reversal of 16620389 is 98302661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16620389 is a prime.

It is a super-2 number, since 2×16620389² = 552474661022642, 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 (16620349) 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, 80579 + ... + 80784.

It is an arithmetic number, because the mean of its divisors is an integer number (4195464).

Almost surely, 2^16620389 is an apocalyptic number.

It is an amenable number.

16620389 is a deficient number, since it is larger than the sum of its proper divisors (161467).

16620389 is a wasteful number, since it uses less digits than its factorization.

16620389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161466.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 16620389 is about 4076.8111312642. The cubic root of 16620389 is about 255.1998382238.

The spelling of 16620389 in words is "sixteen million, six hundred twenty thousand, three hundred eighty-nine".