2101220401997 has 2 divisors, whose sum is σ = 2101220401998. Its totient is φ = 2101220401996.

The previous prime is 2101220401991. The next prime is 2101220402033. The reversal of 2101220401997 is 7991040221012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2086851824836 + 14368577161 = 1444594^2 + 119869^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101220401997 - 2⁴ = 2101220401981 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2101220401997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2101220401991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1050610200998 + 1050610200999.

It is an arithmetic number, because the mean of its divisors is an integer number (1050610200999).

Almost surely, 2^{2101220401997} is an apocalyptic number.

It is an amenable number.

2101220401997 is a deficient number, since it is larger than the sum of its proper divisors (1).

2101220401997 is an equidigital number, since it uses as much as digits as its factorization.

2101220401997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 38.

The spelling of 2101220401997 in words is "two trillion, one hundred one billion, two hundred twenty million, four hundred one thousand, nine hundred ninety-seven".