21887340 has 48 divisors (see below), whose sum is σ = 61592832. Its totient is φ = 5807296.

The previous prime is 21887339. The next prime is 21887351. The reversal of 21887340 is 4378812.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12817 + ... + 14423.

It is an arithmetic number, because the mean of its divisors is an integer number (1283184).

Almost surely, 2^21887340 is an apocalyptic number.

21887340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21887340 is an abundant number, since it is smaller than the sum of its proper divisors (39705492).

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

21887340 is a wasteful number, since it uses less digits than its factorization.

21887340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1846 (or 1844 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 21887340 is about 4678.3907489649. The cubic root of 21887340 is about 279.7248146692.

The spelling of 21887340 in words is "twenty-one million, eight hundred eighty-seven thousand, three hundred forty".