21053030 has 32 divisors (see below), whose sum is σ = 39529728. Its totient is φ = 8064000.

The previous prime is 21053017. The next prime is 21053041. The reversal of 21053030 is 3035012.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21052996 and 21053014.

It is a congruent number.

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, 34730 + ... + 35330.

It is an arithmetic number, because the mean of its divisors is an integer number (1235304).

Almost surely, 2^21053030 is an apocalyptic number.

21053030 is a deficient number, since it is larger than the sum of its proper divisors (18476698).

21053030 is a wasteful number, since it uses less digits than its factorization.

21053030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 752.

The product of its (nonzero) digits is 90, while the sum is 14.

The square root of 21053030 is about 4588.3580941335. The cubic root of 21053030 is about 276.1244537798.

Adding to 21053030 its reverse (3035012), we get a palindrome (24088042).

The spelling of 21053030 in words is "twenty-one million, fifty-three thousand, thirty".