400197720 has 128 divisors (see below), whose sum is σ = 1324693440. Its totient is φ = 96092160.

The previous prime is 400197713. The next prime is 400197739. The reversal of 400197720 is 27791004.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60832 + ... + 67088.

Almost surely, 2^400197720 is an apocalyptic number.

400197720 is a gapful number since it is divisible by the number (40) 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 400197720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (662346720).

400197720 is an abundant number, since it is smaller than the sum of its proper divisors (924495720).

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

400197720 is a wasteful number, since it uses less digits than its factorization.

400197720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6325 (or 6321 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 30.

The square root of 400197720 is about 20004.9423893197. The cubic root of 400197720 is about 736.9276808487.

The spelling of 400197720 in words is "four hundred million, one hundred ninety-seven thousand, seven hundred twenty".