399761643 has 16 divisors (see below), whose sum is σ = 561600000. Its totient is φ = 252441024.

The previous prime is 399761641. The next prime is 399761657. The reversal of 399761643 is 346167993.

It is not a de Polignac number, because 399761643 - 2¹ = 399761641 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 399761592 and 399761601.

It is not an unprimeable number, because it can be changed into a prime (399761641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21018 + ... + 35231.

It is an arithmetic number, because the mean of its divisors is an integer number (35100000).

Almost surely, 2^399761643 is an apocalyptic number.

399761643 is a deficient number, since it is larger than the sum of its proper divisors (161838357).

399761643 is a wasteful number, since it uses less digits than its factorization.

399761643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56378.

The product of its digits is 734832, while the sum is 48.

The square root of 399761643 is about 19994.0401870157. The cubic root of 399761643 is about 736.6599181990.

The spelling of 399761643 in words is "three hundred ninety-nine million, seven hundred sixty-one thousand, six hundred forty-three".