5639803721 has 2 divisors, whose sum is σ = 5639803722. Its totient is φ = 5639803720.

The previous prime is 5639803691. The next prime is 5639803727. The reversal of 5639803721 is 1273089365.

5639803721 is digitally balanced in base 3, because in such base 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., 4845691321 + 794112400 = 69611^2 + 28180^2 .

It is a cyclic number.

It is not a de Polignac number, because 5639803721 - 2¹⁰ = 5639802697 is a prime.

It is a super-2 number, since 2×5639803721² = 63614772022810891682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (5639803727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2819901860 + 2819901861.

It is an arithmetic number, because the mean of its divisors is an integer number (2819901861).

Almost surely, 2^5639803721 is an apocalyptic number.

It is an amenable number.

5639803721 is a deficient number, since it is larger than the sum of its proper divisors (1).

5639803721 is an equidigital number, since it uses as much as digits as its factorization.

5639803721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 272160, while the sum is 44.

The square root of 5639803721 is about 75098.6266252586. The cubic root of 5639803721 is about 1780.0054413207.

The spelling of 5639803721 in words is "five billion, six hundred thirty-nine million, eight hundred three thousand, seven hundred twenty-one".