401540240 has 20 divisors (see below), whose sum is σ = 933581244. Its totient is φ = 160616064.

The previous prime is 401540239. The next prime is 401540263. The reversal of 401540240 is 42045104.

It can be written as a sum of positive squares in 2 ways, for example, as 305970064 + 95570176 = 17492^2 + 9776^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×401540240² = 322469128678515200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2509547 + ... + 2509706.

Almost surely, 2^401540240 is an apocalyptic number.

401540240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

401540240 is an abundant number, since it is smaller than the sum of its proper divisors (532041004).

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

401540240 is a wasteful number, since it uses less digits than its factorization.

401540240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5019266 (or 5019260 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 401540240 is about 20038.4690033944. The cubic root of 401540240 is about 737.7508039068.

Adding to 401540240 its reverse (42045104), we get a palindrome (443585344).

The spelling of 401540240 in words is "four hundred one million, five hundred forty thousand, two hundred forty".