21052870 has 8 divisors (see below), whose sum is σ = 37895184. Its totient is φ = 8421144.

The previous prime is 21052853. The next prime is 21052877. The reversal of 21052870 is 7825012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21052877) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1052634 + ... + 1052653.

It is an arithmetic number, because the mean of its divisors is an integer number (4736898).

Almost surely, 2^21052870 is an apocalyptic number.

21052870 is a deficient number, since it is larger than the sum of its proper divisors (16842314).

21052870 is a wasteful number, since it uses less digits than its factorization.

21052870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2105294.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 21052870 is about 4588.3406586695. The cubic root of 21052870 is about 276.1237542760.

Adding to 21052870 its reverse (7825012), we get a palindrome (28877882).

The spelling of 21052870 in words is "twenty-one million, fifty-two thousand, eight hundred seventy".