21020020330 has 8 divisors (see below), whose sum is σ = 37836036612. Its totient is φ = 8408008128.

The previous prime is 21020020319. The next prime is 21020020337. The reversal of 21020020330 is 3302002012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18728196201 + 2291824129 = 136851^2 + 47873^2 .

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

It is a super-2 number, since 2×21020020330² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21020020330.

It is not an unprimeable number, because it can be changed into a prime (21020020337) 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, 1051001007 + ... + 1051001026.

Almost surely, 2^21020020330 is an apocalyptic number.

21020020330 is a deficient number, since it is larger than the sum of its proper divisors (16816016282).

21020020330 is a wasteful number, since it uses less digits than its factorization.

21020020330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2102002040.

The product of its (nonzero) digits is 72, while the sum is 13.

Adding to 21020020330 its reverse (3302002012), we get a palindrome (24322022342).

The spelling of 21020020330 in words is "twenty-one billion, twenty million, twenty thousand, three hundred thirty".