720912212021 has 2 divisors, whose sum is σ = 720912212022. Its totient is φ = 720912212020.

The previous prime is 720912211993. The next prime is 720912212039. The reversal of 720912212021 is 120212219027.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 389238732100 + 331673479921 = 623890^2 + 575911^2 .

It is a cyclic number.

It is not a de Polignac number, because 720912212021 - 2¹⁴ = 720912195637 is a prime.

It is a super-2 number, since 2×720912212021² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (720912212051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360456106010 + 360456106011.

It is an arithmetic number, because the mean of its divisors is an integer number (360456106011).

Almost surely, 2^720912212021 is an apocalyptic number.

It is an amenable number.

720912212021 is a deficient number, since it is larger than the sum of its proper divisors (1).

720912212021 is an equidigital number, since it uses as much as digits as its factorization.

720912212021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 29.

The spelling of 720912212021 in words is "seven hundred twenty billion, nine hundred twelve million, two hundred twelve thousand, twenty-one".