21870060 has 48 divisors (see below), whose sum is σ = 63352800. Its totient is φ = 5630464.

The previous prime is 21870053. The next prime is 21870091. The reversal of 21870060 is 6007812.

It is a self number, because there is not a number n which added to its sum of digits gives 21870060.

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, 4545 + ... + 8024.

It is an arithmetic number, because the mean of its divisors is an integer number (1319850).

Almost surely, 2^21870060 is an apocalyptic number.

21870060 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21870060 is an abundant number, since it is smaller than the sum of its proper divisors (41482740).

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

21870060 is a wasteful number, since it uses less digits than its factorization.

21870060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12610 (or 12608 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 21870060 is about 4676.5435954346. The cubic root of 21870060 is about 279.6511812749.

Adding to 21870060 its reverse (6007812), we get a palindrome (27877872).

The spelling of 21870060 in words is "twenty-one million, eight hundred seventy thousand, sixty".