3921122021 has 2 divisors, whose sum is σ = 3921122022. Its totient is φ = 3921122020.

The previous prime is 3921122011. The next prime is 3921122047. The reversal of 3921122021 is 1202211293.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2652765025 + 1268356996 = 51505^2 + 35614^2 .

It is an emirp because it is prime and its reverse (1202211293) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3921122021 is a prime.

It is a super-2 number, since 2×3921122021² = 30750395807142248882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3921122011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1960561010 + 1960561011.

It is an arithmetic number, because the mean of its divisors is an integer number (1960561011).

Almost surely, 2^3921122021 is an apocalyptic number.

It is an amenable number.

3921122021 is a deficient number, since it is larger than the sum of its proper divisors (1).

3921122021 is an equidigital number, since it uses as much as digits as its factorization.

3921122021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 3921122021 is about 62618.8631404308. The cubic root of 3921122021 is about 1576.8974556240.

The spelling of 3921122021 in words is "three billion, nine hundred twenty-one million, one hundred twenty-two thousand, twenty-one".