20021161597 has 2 divisors, whose sum is σ = 20021161598. Its totient is φ = 20021161596.

The previous prime is 20021161483. The next prime is 20021161603. The reversal of 20021161597 is 79516112002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19980953316 + 40208281 = 141354^2 + 6341^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021161597 - 2⁷ = 20021161469 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20021111597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010580798 + 10010580799.

It is an arithmetic number, because the mean of its divisors is an integer number (10010580799).

Almost surely, 2^20021161597 is an apocalyptic number.

It is an amenable number.

20021161597 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021161597 is an equidigital number, since it uses as much as digits as its factorization.

20021161597 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7560, while the sum is 34.

Adding to 20021161597 its reverse (79516112002), we get a palindrome (99537273599).

The spelling of 20021161597 in words is "twenty billion, twenty-one million, one hundred sixty-one thousand, five hundred ninety-seven".