4006651021 has 2 divisors, whose sum is σ = 4006651022. Its totient is φ = 4006651020.

The previous prime is 4006650997. The next prime is 4006651031. The reversal of 4006651021 is 1201566004.

4006651021 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3888146025 + 118504996 = 62355^2 + 10886^2 .

It is a cyclic number.

It is not a de Polignac number, because 4006651021 - 2⁹ = 4006650509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4006651031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2003325510 + 2003325511.

It is an arithmetic number, because the mean of its divisors is an integer number (2003325511).

Almost surely, 2^4006651021 is an apocalyptic number.

It is an amenable number.

4006651021 is a deficient number, since it is larger than the sum of its proper divisors (1).

4006651021 is an equidigital number, since it uses as much as digits as its factorization.

4006651021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 4006651021 is about 63298.1123020268. The cubic root of 4006651021 is about 1588.2803845875.

The spelling of 4006651021 in words is "four billion, six million, six hundred fifty-one thousand, twenty-one".