21020121011210 has 8 divisors (see below), whose sum is σ = 37836217820196. Its totient is φ = 8408048404480.

The previous prime is 21020121011189. The next prime is 21020121011269. The reversal of 21020121011210 is 1211012102012.

It can be written as a sum of positive squares in 2 ways, for example, as 18769091893561 + 2251029117649 = 4332331^2 + 1500343^2 .

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

It is a super-2 number, since 2×21020121011210² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1051006050551 + ... + 1051006050570.

Almost surely, 2^{21020121011210} is an apocalyptic number.

21020121011210 is a deficient number, since it is larger than the sum of its proper divisors (16816096808986).

21020121011210 is a wasteful number, since it uses less digits than its factorization.

21020121011210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2102012101128.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21020121011210 its reverse (1211012102012), we get a palindrome (22231133113222).

The spelling of 21020121011210 in words is "twenty-one trillion, twenty billion, one hundred twenty-one million, eleven thousand, two hundred ten".