4009485721 has 2 divisors, whose sum is σ = 4009485722. Its totient is φ = 4009485720.

The previous prime is 4009485713. The next prime is 4009485761. The reversal of 4009485721 is 1275849004.

It is an a-pointer prime, because the next prime (4009485761) can be obtained adding 4009485721 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3394693696 + 614792025 = 58264^2 + 24795^2 .

It is a cyclic number.

It is not a de Polignac number, because 4009485721 - 2³ = 4009485713 is a prime.

It is the 63321-st Hogben number.

It is not a weakly prime, because it can be changed into another prime (4009485761) by changing a digit.

It is a nontrivial repunit in base 63320.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2004742860 + 2004742861.

It is an arithmetic number, because the mean of its divisors is an integer number (2004742861).

Almost surely, 2^4009485721 is an apocalyptic number.

It is an amenable number.

4009485721 is a deficient number, since it is larger than the sum of its proper divisors (1).

4009485721 is an equidigital number, since it uses as much as digits as its factorization.

4009485721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 4009485721 is about 63320.5000059223. The cubic root of 4009485721 is about 1588.6548650043.

The spelling of 4009485721 in words is "four billion, nine million, four hundred eighty-five thousand, seven hundred twenty-one".