16621967 has 2 divisors, whose sum is σ = 16621968. Its totient is φ = 16621966.

The previous prime is 16621949. The next prime is 16622009. The reversal of 16621967 is 76912661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16621967 - 2¹⁰ = 16620943 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16621967.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16621567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8310983 + 8310984.

It is an arithmetic number, because the mean of its divisors is an integer number (8310984).

Almost surely, 2^16621967 is an apocalyptic number.

16621967 is a deficient number, since it is larger than the sum of its proper divisors (1).

16621967 is an equidigital number, since it uses as much as digits as its factorization.

16621967 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 38.

The square root of 16621967 is about 4077.0046602868. The cubic root of 16621967 is about 255.2079145009.

Subtracting from 16621967 its sum of digits (38), we obtain a square (16621929 = 4077²).

The spelling of 16621967 in words is "sixteen million, six hundred twenty-one thousand, nine hundred sixty-seven".