21111021101210 has 8 divisors (see below), whose sum is σ = 37999837982196. Its totient is φ = 8444408440480.

The previous prime is 21111021101189. The next prime is 21111021101221. The reversal of 21111021101210 is 1210112011112.

It can be written as a sum of positive squares in 2 ways, for example, as 20433301943041 + 677719158169 = 4520321^2 + 823237^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1055551055051 + ... + 1055551055070.

Almost surely, 2^{21111021101210} is an apocalyptic number.

21111021101210 is a deficient number, since it is larger than the sum of its proper divisors (16888816880986).

21111021101210 is a wasteful number, since it uses less digits than its factorization.

21111021101210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2111102110128.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21111021101210 its reverse (1210112011112), we get a palindrome (22321133112322).

The spelling of 21111021101210 in words is "twenty-one trillion, one hundred eleven billion, twenty-one million, one hundred one thousand, two hundred ten".