399989881472 has 32 divisors (see below), whose sum is σ = 799400784180. Its totient is φ = 199355959296.

The previous prime is 399989881471. The next prime is 399989881523. The reversal of 399989881472 is 274188989993.

It can be written as a sum of positive squares in 2 ways, for example, as 338100383296 + 61889498176 = 581464^2 + 248776^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 399989881393 and 399989881402.

It is not an unprimeable number, because it can be changed into a prime (399989881471) 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, 4951823 + ... + 5031950.

Almost surely, 2^399989881472 is an apocalyptic number.

399989881472 is a gapful number since it is divisible by the number (32) formed by its first and last digit.

It is an amenable number.

399989881472 is a deficient number, since it is larger than the sum of its proper divisors (399410902708).

399989881472 is an equidigital number, since it uses as much as digits as its factorization.

399989881472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9984100 (or 9984088 counting only the distinct ones).

The product of its digits is 564350976, while the sum is 77.

The spelling of 399989881472 in words is "three hundred ninety-nine billion, nine hundred eighty-nine million, eight hundred eighty-one thousand, four hundred seventy-two".