398139742 has 64 divisors (see below), whose sum is σ = 813431808. Its totient is φ = 141120000.

The previous prime is 398139653. The next prime is 398139751. The reversal of 398139742 is 247931893.

It is a super-3 number, since 3×398139742³ (a number of 27 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 398139692 and 398139701.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 140742 + ... + 143542.

It is an arithmetic number, because the mean of its divisors is an integer number (12709872).

Almost surely, 2^398139742 is an apocalyptic number.

398139742 is an abundant number, since it is smaller than the sum of its proper divisors (415292066).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398139742 is a wasteful number, since it uses less digits than its factorization.

398139742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2905.

The product of its digits is 326592, while the sum is 46.

The square root of 398139742 is about 19953.4393526530. The cubic root of 398139742 is about 735.6623162928.

The spelling of 398139742 in words is "three hundred ninety-eight million, one hundred thirty-nine thousand, seven hundred forty-two".