4021920901 has 2 divisors, whose sum is σ = 4021920902. Its totient is φ = 4021920900.

The previous prime is 4021920863. The next prime is 4021920907. The reversal of 4021920901 is 1090291204.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2541672225 + 1480248676 = 50415^2 + 38474^2 .

It is a cyclic number.

It is not a de Polignac number, because 4021920901 - 2⁹ = 4021920389 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 4021920901.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4021920907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2010960450 + 2010960451.

It is an arithmetic number, because the mean of its divisors is an integer number (2010960451).

Almost surely, 2^4021920901 is an apocalyptic number.

It is an amenable number.

4021920901 is a deficient number, since it is larger than the sum of its proper divisors (1).

4021920901 is an equidigital number, since it uses as much as digits as its factorization.

4021920901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 4021920901 is about 63418.6163598671. The cubic root of 4021920901 is about 1590.2955426785.

The spelling of 4021920901 in words is "four billion, twenty-one million, nine hundred twenty thousand, nine hundred one".