3959463721 has 4 divisors (see below), whose sum is σ = 4066476292. Its totient is φ = 3852451152.

The previous prime is 3959463689. The next prime is 3959463737. The reversal of 3959463721 is 1273649593.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1752343321 + 2207120400 = 41861^2 + 46980^2 .

It is a cyclic number.

It is not a de Polignac number, because 3959463721 - 2⁵ = 3959463689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3959463791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53506230 + ... + 53506303.

It is an arithmetic number, because the mean of its divisors is an integer number (1016619073).

Almost surely, 2^3959463721 is an apocalyptic number.

It is an amenable number.

3959463721 is a deficient number, since it is larger than the sum of its proper divisors (107012571).

3959463721 is a wasteful number, since it uses less digits than its factorization.

3959463721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107012570.

The product of its digits is 1224720, while the sum is 49.

The square root of 3959463721 is about 62924.2697295725. The cubic root of 3959463721 is about 1582.0205577329.

The spelling of 3959463721 in words is "three billion, nine hundred fifty-nine million, four hundred sixty-three thousand, seven hundred twenty-one".