397992291840 has 960 divisors, whose sum is σ = 1635189716160. Its totient is φ = 88190484480.

The previous prime is 397992291839. The next prime is 397992291863. The reversal of 397992291840 is 48192299793.

397992291840 is a `hidden beast` number, since 397 + 9 + 9 + 229 + 18 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (960).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 372302826 + ... + 372303894.

It is an arithmetic number, because the mean of its divisors is an integer number (1703322621).

Almost surely, 2^397992291840 is an apocalyptic number.

397992291840 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 397992291840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (817594858080).

397992291840 is an abundant number, since it is smaller than the sum of its proper divisors (1237197424320).

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

397992291840 is a wasteful number, since it uses less digits than its factorization.

397992291840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1235 (or 1216 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 397992291840 in words is "three hundred ninety-seven billion, nine hundred ninety-two million, two hundred ninety-one thousand, eight hundred forty".