20801567 has 2 divisors, whose sum is σ = 20801568. Its totient is φ = 20801566.

The previous prime is 20801507. The next prime is 20801579. The reversal of 20801567 is 76510802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20801567 - 2¹⁰ = 20800543 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20801507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10400783 + 10400784.

It is an arithmetic number, because the mean of its divisors is an integer number (10400784).

Almost surely, 2^20801567 is an apocalyptic number.

20801567 is a deficient number, since it is larger than the sum of its proper divisors (1).

20801567 is an equidigital number, since it uses as much as digits as its factorization.

20801567 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 29.

The square root of 20801567 is about 4560.8734909006. The cubic root of 20801567 is about 275.0206794366.

The spelling of 20801567 in words is "twenty million, eight hundred one thousand, five hundred sixty-seven".