16401840 has 160 divisors (see below), whose sum is σ = 62662656. Its totient is φ = 3456000.

The previous prime is 16401839. The next prime is 16401871. The reversal of 16401840 is 4810461.

16401840 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×16401840³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 16401840.

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, 21465 + ... + 22215.

Almost surely, 2^16401840 is an apocalyptic number.

16401840 is a gapful number since it is divisible by the number (10) 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 16401840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31331328).

16401840 is an abundant number, since it is smaller than the sum of its proper divisors (46260816).

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

16401840 is a wasteful number, since it uses less digits than its factorization.

16401840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787 (or 781 counting only the distinct ones).

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

The square root of 16401840 is about 4049.9185176988. The cubic root of 16401840 is about 254.0763198851.

It can be divided in two parts, 16 and 401840, that added together give a triangular number (401856 = T₈₉₆).

The spelling of 16401840 in words is "sixteen million, four hundred one thousand, eight hundred forty".