20372591 has 2 divisors, whose sum is σ = 20372592. Its totient is φ = 20372590.

The previous prime is 20372581. The next prime is 20372659. The reversal of 20372591 is 19527302.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20372591 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20372581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10186295 + 10186296.

It is an arithmetic number, because the mean of its divisors is an integer number (10186296).

Almost surely, 2^20372591 is an apocalyptic number.

20372591 is a deficient number, since it is larger than the sum of its proper divisors (1).

20372591 is an equidigital number, since it uses as much as digits as its factorization.

20372591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 20372591 is about 4513.6006690889. The cubic root of 20372591 is about 273.1170138892.

Adding to 20372591 its reverse (19527302), we get a palindrome (39899893).

The spelling of 20372591 in words is "twenty million, three hundred seventy-two thousand, five hundred ninety-one".