4001388 has 12 divisors (see below), whose sum is σ = 9336600. Its totient is φ = 1333792.

The previous prime is 4001383. The next prime is 4001399. The reversal of 4001388 is 8831004.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×4001388² = 32022211853088, which contains 22 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (4001383) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166713 + ... + 166736.

It is an arithmetic number, because the mean of its divisors is an integer number (778050).

Almost surely, 2^4001388 is an apocalyptic number.

It is an amenable number.

4001388 is an abundant number, since it is smaller than the sum of its proper divisors (5335212).

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

4001388 is a wasteful number, since it uses less digits than its factorization.

4001388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333456 (or 333454 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 4001388 is about 2000.3469699030. The cubic root of 4001388 is about 158.7584640123.

The spelling of 4001388 in words is "four million, one thousand, three hundred eighty-eight".