20621667 has 12 divisors (see below), whose sum is σ = 30222920. Its totient is φ = 12497760.

The previous prime is 20621609. The next prime is 20621677. The reversal of 20621667 is 76612602.

It is not a de Polignac number, because 20621667 - 2¹⁹ = 20097379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20621677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28042 + ... + 28767.

Almost surely, 2^20621667 is an apocalyptic number.

20621667 is a deficient number, since it is larger than the sum of its proper divisors (9601253).

20621667 is a wasteful number, since it uses less digits than its factorization.

20621667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56834 (or 56823 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 20621667 is about 4541.1085650973. The cubic root of 20621667 is about 274.2255544135.

The spelling of 20621667 in words is "twenty million, six hundred twenty-one thousand, six hundred sixty-seven".