20859610091 has 2 divisors, whose sum is σ = 20859610092. Its totient is φ = 20859610090.

The previous prime is 20859610069. The next prime is 20859610127. The reversal of 20859610091 is 19001695802.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20859610091 - 2²² = 20855415787 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20859640091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10429805045 + 10429805046.

It is an arithmetic number, because the mean of its divisors is an integer number (10429805046).

Almost surely, 2^20859610091 is an apocalyptic number.

20859610091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20859610091 is an equidigital number, since it uses as much as digits as its factorization.

20859610091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 41.

The spelling of 20859610091 in words is "twenty billion, eight hundred fifty-nine million, six hundred ten thousand, ninety-one".