20002121197 has 4 divisors (see below), whose sum is σ = 20023469116. Its totient is φ = 19980773280.

The previous prime is 20002121179. The next prime is 20002121203. The reversal of 20002121197 is 79112120002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9056567556 + 10945553641 = 95166^2 + 104621^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20002121197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20002121147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10672554 + ... + 10674427.

It is an arithmetic number, because the mean of its divisors is an integer number (5005867279).

Almost surely, 2^20002121197 is an apocalyptic number.

It is an amenable number.

20002121197 is a deficient number, since it is larger than the sum of its proper divisors (21347919).

20002121197 is an equidigital number, since it uses as much as digits as its factorization.

20002121197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21347918.

The product of its (nonzero) digits is 504, while the sum is 25.

Adding to 20002121197 its reverse (79112120002), we get a palindrome (99114241199).

The spelling of 20002121197 in words is "twenty billion, two million, one hundred twenty-one thousand, one hundred ninety-seven".