21862040 has 32 divisors (see below), whose sum is σ = 49870080. Its totient is φ = 8623872.

The previous prime is 21862031. The next prime is 21862063. The reversal of 21862040 is 4026812.

It is a junction number, because it is equal to n+sod(n) for n = 21861997 and 21862015.

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, 824 + ... + 6663.

It is an arithmetic number, because the mean of its divisors is an integer number (1558440).

Almost surely, 2^21862040 is an apocalyptic number.

21862040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21862040 is an abundant number, since it is smaller than the sum of its proper divisors (28008040).

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

21862040 is a wasteful number, since it uses less digits than its factorization.

21862040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7571 (or 7567 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 21862040 is about 4675.6860459188. The cubic root of 21862040 is about 279.6169933382.

Adding to 21862040 its reverse (4026812), we get a palindrome (25888852).

The spelling of 21862040 in words is "twenty-one million, eight hundred sixty-two thousand, forty".