20764619 has 2 divisors, whose sum is σ = 20764620. Its totient is φ = 20764618.

The previous prime is 20764591. The next prime is 20764651. The reversal of 20764619 is 91646702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20764619 - 2²⁰ = 19716043 is a prime.

It is a super-2 number, since 2×20764619² = 862338804430322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20761619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10382309 + 10382310.

It is an arithmetic number, because the mean of its divisors is an integer number (10382310).

Almost surely, 2^20764619 is an apocalyptic number.

20764619 is a deficient number, since it is larger than the sum of its proper divisors (1).

20764619 is an equidigital number, since it uses as much as digits as its factorization.

20764619 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 20764619 is about 4556.8211507585. The cubic root of 20764619 is about 274.8577512253.

The spelling of 20764619 in words is "twenty million, seven hundred sixty-four thousand, six hundred nineteen".