393962661 has 6 divisors (see below), whose sum is σ = 569057190. Its totient is φ = 262641768.

The previous prime is 393962629. The next prime is 393962707. The reversal of 393962661 is 166269393.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 368409636 + 25553025 = 19194^2 + 5055^2 .

It is not a de Polignac number, because 393962661 - 2⁵ = 393962629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (393962161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21886806 + ... + 21886823.

It is an arithmetic number, because the mean of its divisors is an integer number (94842865).

Almost surely, 2^393962661 is an apocalyptic number.

It is an amenable number.

393962661 is a deficient number, since it is larger than the sum of its proper divisors (175094529).

393962661 is a wasteful number, since it uses less digits than its factorization.

393962661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43773635 (or 43773632 counting only the distinct ones).

The product of its digits is 314928, while the sum is 45.

The square root of 393962661 is about 19848.4926631722. The cubic root of 393962661 is about 733.0805337769.

The spelling of 393962661 in words is "three hundred ninety-three million, nine hundred sixty-two thousand, six hundred sixty-one".