399885749 has 2 divisors, whose sum is σ = 399885750. Its totient is φ = 399885748.

The previous prime is 399885671. The next prime is 399885791. The reversal of 399885749 is 947588993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 301022500 + 98863249 = 17350^2 + 9943^2 .

It is a cyclic number.

It is not a de Polignac number, because 399885749 - 2¹² = 399881653 is a prime.

It is a super-2 number, since 2×399885749² = 319817224506582002, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 399885691 and 399885700.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (399885349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199942874 + 199942875.

It is an arithmetic number, because the mean of its divisors is an integer number (199942875).

Almost surely, 2^399885749 is an apocalyptic number.

It is an amenable number.

399885749 is a deficient number, since it is larger than the sum of its proper divisors (1).

399885749 is an equidigital number, since it uses as much as digits as its factorization.

399885749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19595520, while the sum is 62.

The square root of 399885749 is about 19997.1435210132. The cubic root of 399885749 is about 736.7361423342.

The spelling of 399885749 in words is "three hundred ninety-nine million, eight hundred eighty-five thousand, seven hundred forty-nine".