20215667 has 2 divisors, whose sum is σ = 20215668. Its totient is φ = 20215666.

The previous prime is 20215661. The next prime is 20215681. The reversal of 20215667 is 76651202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20215667 - 2⁶ = 20215603 is a prime.

It is not a weakly prime, because it can be changed into another prime (20215661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10107833 + 10107834.

It is an arithmetic number, because the mean of its divisors is an integer number (10107834).

Almost surely, 2^20215667 is an apocalyptic number.

20215667 is a deficient number, since it is larger than the sum of its proper divisors (1).

20215667 is an equidigital number, since it uses as much as digits as its factorization.

20215667 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 20215667 is about 4496.1836039023. The cubic root of 20215667 is about 272.4139593129.

Adding to 20215667 its reverse (76651202), we get a palindrome (96866869).

The spelling of 20215667 in words is "twenty million, two hundred fifteen thousand, six hundred sixty-seven".