398434029840 has 800 divisors, whose sum is σ = 1781006008320. Its totient is φ = 80117683200.

The previous prime is 398434029811. The next prime is 398434029859. The reversal of 398434029840 is 48920434893.

398434029840 is a `hidden beast` number, since 3 + 9 + 8 + 4 + 340 + 298 + 4 + 0 = 666.

It is a super-2 number, since 2×398434029840² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 15454881 + ... + 15480639.

Almost surely, 2^398434029840 is an apocalyptic number.

398434029840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 398434029840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (890503004160).

398434029840 is an abundant number, since it is smaller than the sum of its proper divisors (1382571978480).

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

398434029840 is a wasteful number, since it uses less digits than its factorization.

398434029840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25833 (or 25818 counting only the distinct ones).

The product of its (nonzero) digits is 5971968, while the sum is 54.

The spelling of 398434029840 in words is "three hundred ninety-eight billion, four hundred thirty-four million, twenty-nine thousand, eight hundred forty".