16621240 has 32 divisors (see below), whose sum is σ = 39599280. Its totient is φ = 6257152.

The previous prime is 16621229. The next prime is 16621259. The reversal of 16621240 is 4212661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11542 + ... + 12901.

Almost surely, 2^16621240 is an apocalyptic number.

16621240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16621240 is an abundant number, since it is smaller than the sum of its proper divisors (22978040).

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

16621240 is a wasteful number, since it uses less digits than its factorization.

16621240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24471 (or 24467 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 16621240 is about 4076.9155007186. The cubic root of 16621240 is about 255.2041937447.

It can be divided in two parts, 16621 and 240, that added together give a palindrome (16861).

The spelling of 16621240 in words is "sixteen million, six hundred twenty-one thousand, two hundred forty".