399193251949 has 8 divisors (see below), whose sum is σ = 422693580600. Its totient is φ = 375694964736.

The previous prime is 399193251929. The next prime is 399193251953. The reversal of 399193251949 is 949152391993.

It can be written as a sum of positive squares in 4 ways, for example, as 10619302500 + 388573949449 = 103050^2 + 623357^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 399193251949 - 2⁵ = 399193251917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399193251929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98244 + ... + 898909.

It is an arithmetic number, because the mean of its divisors is an integer number (52836697575).

Almost surely, 2^399193251949 is an apocalyptic number.

It is an amenable number.

399193251949 is a deficient number, since it is larger than the sum of its proper divisors (23500328651).

399193251949 is a wasteful number, since it uses less digits than its factorization.

399193251949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1020719.

The product of its digits is 21257640, while the sum is 64.

The spelling of 399193251949 in words is "three hundred ninety-nine billion, one hundred ninety-three million, two hundred fifty-one thousand, nine hundred forty-nine".