21041970 has 16 divisors (see below), whose sum is σ = 50500800. Its totient is φ = 5611184.

The previous prime is 21041879. The next prime is 21041981. The reversal of 21041970 is 7914012.

It is a self number, because there is not a number n which added to its sum of digits gives 21041970.

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, 350670 + ... + 350729.

It is an arithmetic number, because the mean of its divisors is an integer number (3156300).

Almost surely, 2^21041970 is an apocalyptic number.

21041970 is an abundant number, since it is smaller than the sum of its proper divisors (29458830).

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

21041970 is a wasteful number, since it uses less digits than its factorization.

21041970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 701409.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 21041970 is about 4587.1527116502. The cubic root of 21041970 is about 276.0760922312.

Adding to 21041970 its reverse (7914012), we get a palindrome (28955982).

The spelling of 21041970 in words is "twenty-one million, forty-one thousand, nine hundred seventy".