20712997 has 2 divisors, whose sum is σ = 20712998. Its totient is φ = 20712996.

The previous prime is 20712973. The next prime is 20713003. The reversal of 20712997 is 79921702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20196036 + 516961 = 4494^2 + 719^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20712997 is a 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 (20712917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10356498 + 10356499.

It is an arithmetic number, because the mean of its divisors is an integer number (10356499).

Almost surely, 2^20712997 is an apocalyptic number.

It is an amenable number.

20712997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20712997 is an equidigital number, since it uses as much as digits as its factorization.

20712997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 20712997 is about 4551.1533703008. The cubic root of 20712997 is about 274.6297916518.

The spelling of 20712997 in words is "twenty million, seven hundred twelve thousand, nine hundred ninety-seven".