20735591 has 2 divisors, whose sum is σ = 20735592. Its totient is φ = 20735590.

The previous prime is 20735587. The next prime is 20735623. The reversal of 20735591 is 19553702.

It is an a-pointer prime, because the next prime (20735623) can be obtained adding 20735591 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20735591 - 2² = 20735587 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20735521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10367795 + 10367796.

It is an arithmetic number, because the mean of its divisors is an integer number (10367796).

Almost surely, 2^20735591 is an apocalyptic number.

20735591 is a deficient number, since it is larger than the sum of its proper divisors (1).

20735591 is an equidigital number, since it uses as much as digits as its factorization.

20735591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9450, while the sum is 32.

The square root of 20735591 is about 4553.6349216862. The cubic root of 20735591 is about 274.7296119196.

The spelling of 20735591 in words is "twenty million, seven hundred thirty-five thousand, five hundred ninety-one".