398961993 has 16 divisors (see below), whose sum is σ = 545965056. Its totient is φ = 259057680.

The previous prime is 398961973. The next prime is 398962027. The reversal of 398961993 is 399169893.

It is not a de Polignac number, because 398961993 - 2¹³ = 398953801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (398961973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6396 + ... + 28962.

It is an arithmetic number, because the mean of its divisors is an integer number (34122816).

Almost surely, 2^398961993 is an apocalyptic number.

It is an amenable number.

398961993 is a deficient number, since it is larger than the sum of its proper divisors (147003063).

398961993 is a wasteful number, since it uses less digits than its factorization.

398961993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22724.

The product of its digits is 2834352, while the sum is 57.

The square root of 398961993 is about 19974.0329678310. The cubic root of 398961993 is about 736.1684058803.

The spelling of 398961993 in words is "three hundred ninety-eight million, nine hundred sixty-one thousand, nine hundred ninety-three".