20610091 has 2 divisors, whose sum is σ = 20610092. Its totient is φ = 20610090.

The previous prime is 20610089. The next prime is 20610113. The reversal of 20610091 is 19001602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20610091 - 2¹ = 20610089 is a prime.

Together with 20610089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20610391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10305045 + 10305046.

It is an arithmetic number, because the mean of its divisors is an integer number (10305046).

Almost surely, 2^20610091 is an apocalyptic number.

20610091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20610091 is an equidigital number, since it uses as much as digits as its factorization.

20610091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 20610091 is about 4539.8338075308. The cubic root of 20610091 is about 274.1742325167.

Adding to 20610091 its reverse (19001602), we get a palindrome (39611693).

The spelling of 20610091 in words is "twenty million, six hundred ten thousand, ninety-one".