401991280 has 40 divisors (see below), whose sum is σ = 944283312. Its totient is φ = 159135744.

The previous prime is 401991269. The next prime is 401991287. The reversal of 401991280 is 82199104.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401991287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18142 + ... + 33661.

Almost surely, 2^401991280 is an apocalyptic number.

401991280 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

401991280 is an abundant number, since it is smaller than the sum of its proper divisors (542292032).

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

401991280 is a wasteful number, since it uses less digits than its factorization.

401991280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51913 (or 51907 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 401991280 is about 20049.7201975489. The cubic root of 401991280 is about 738.0269328185.

The spelling of 401991280 in words is "four hundred one million, nine hundred ninety-one thousand, two hundred eighty".