220121019997 has 2 divisors, whose sum is σ = 220121019998. Its totient is φ = 220121019996.

The previous prime is 220121019983. The next prime is 220121020033. The reversal of 220121019997 is 799910121022.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 179427640921 + 40693379076 = 423589^2 + 201726^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-220121019997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220121019917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110060509998 + 110060509999.

It is an arithmetic number, because the mean of its divisors is an integer number (110060509999).

Almost surely, 2^220121019997 is an apocalyptic number.

It is an amenable number.

220121019997 is a deficient number, since it is larger than the sum of its proper divisors (1).

220121019997 is an equidigital number, since it uses as much as digits as its factorization.

220121019997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 43.

The spelling of 220121019997 in words is "two hundred twenty billion, one hundred twenty-one million, nineteen thousand, nine hundred ninety-seven".