399409289641 has 4 divisors (see below), whose sum is σ = 400772461572. Its totient is φ = 398046117712.

The previous prime is 399409289639. The next prime is 399409289651. The reversal of 399409289641 is 146982904993.

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 365324745241 + 34084544400 = 604421^2 + 184620^2 .

It is a cyclic number.

It is not a de Polignac number, because 399409289641 - 2¹ = 399409289639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399409289611) 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, 681585526 + ... + 681586111.

It is an arithmetic number, because the mean of its divisors is an integer number (100193115393).

Almost surely, 2^399409289641 is an apocalyptic number.

It is an amenable number.

399409289641 is a deficient number, since it is larger than the sum of its proper divisors (1363171931).

399409289641 is a wasteful number, since it uses less digits than its factorization.

399409289641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1363171930.

The product of its (nonzero) digits is 30233088, while the sum is 64.

The spelling of 399409289641 in words is "three hundred ninety-nine billion, four hundred nine million, two hundred eighty-nine thousand, six hundred forty-one".