401201640 has 128 divisors (see below), whose sum is σ = 1528416000. Its totient is φ = 91701504.

The previous prime is 401201629. The next prime is 401201657. The reversal of 401201640 is 46102104.

401201640 is a `hidden beast` number, since 4 + 0 + 1 + 20 + 1 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

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, 18975 + ... + 34094.

It is an arithmetic number, because the mean of its divisors is an integer number (11940750).

Almost surely, 2^401201640 is an apocalyptic number.

401201640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

401201640 is an abundant number, since it is smaller than the sum of its proper divisors (1127214360).

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

401201640 is a wasteful number, since it uses less digits than its factorization.

401201640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53096 (or 53086 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 401201640 is about 20030.0184722830. The cubic root of 401201640 is about 737.5433754054.

Adding to 401201640 its reverse (46102104), we get a palindrome (447303744).

The spelling of 401201640 in words is "four hundred one million, two hundred one thousand, six hundred forty".