220121109997 has 2 divisors, whose sum is σ = 220121109998. Its totient is φ = 220121109996.

The previous prime is 220121109961. The next prime is 220121110021. The reversal of 220121109997 is 799901121022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 203226049636 + 16895060361 = 450806^2 + 129981^2 .

It is a cyclic number.

It is not a de Polignac number, because 220121109997 - 2⁷ = 220121109869 is a prime.

It is a super-2 number, since 2×220121109997² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220121109907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110060554998 + 110060554999.

It is an arithmetic number, because the mean of its divisors is an integer number (110060554999).

Almost surely, 2^220121109997 is an apocalyptic number.

It is an amenable number.

220121109997 is a deficient number, since it is larger than the sum of its proper divisors (1).

220121109997 is an equidigital number, since it uses as much as digits as its factorization.

220121109997 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 220121109997 in words is "two hundred twenty billion, one hundred twenty-one million, one hundred nine thousand, nine hundred ninety-seven".