3990121729 has 8 divisors (see below), whose sum is σ = 4445474688. Its totient is φ = 3550204560.

The previous prime is 3990121727. The next prime is 3990121739. The reversal of 3990121729 is 9271210993.

3990121729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3990121729 - 2¹ = 3990121727 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3990121727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3858402 + ... + 3859435.

It is an arithmetic number, because the mean of its divisors is an integer number (555684336).

Almost surely, 2^3990121729 is an apocalyptic number.

It is an amenable number.

3990121729 is a deficient number, since it is larger than the sum of its proper divisors (455352959).

3990121729 is a wasteful number, since it uses less digits than its factorization.

3990121729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7717895.

The product of its (nonzero) digits is 61236, while the sum is 43.

The square root of 3990121729 is about 63167.4103395097. The cubic root of 3990121729 is about 1586.0932433212.

The spelling of 3990121729 in words is "three billion, nine hundred ninety million, one hundred twenty-one thousand, seven hundred twenty-nine".