3962397721 has 4 divisors (see below), whose sum is σ = 3962545444. Its totient is φ = 3962250000.

The previous prime is 3962397671. The next prime is 3962397737. The reversal of 3962397721 is 1277932693.

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 2047110025 + 1915287696 = 45245^2 + 43764^2 .

It is a cyclic number.

It is not a de Polignac number, because 3962397721 - 2⁹ = 3962397209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3962397121) 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, 21030 + ... + 91471.

It is an arithmetic number, because the mean of its divisors is an integer number (990636361).

Almost surely, 2^3962397721 is an apocalyptic number.

It is an amenable number.

3962397721 is a deficient number, since it is larger than the sum of its proper divisors (147723).

3962397721 is a wasteful number, since it uses less digits than its factorization.

3962397721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147722.

The product of its digits is 857304, while the sum is 49.

The square root of 3962397721 is about 62947.5791512271. The cubic root of 3962397721 is about 1582.4112253092.

The spelling of 3962397721 in words is "three billion, nine hundred sixty-two million, three hundred ninety-seven thousand, seven hundred twenty-one".