21111202011021 has 16 divisors (see below), whose sum is σ = 29807076091968. Its totient is φ = 13244899424000.

The previous prime is 21111202011017. The next prime is 21111202011077. The reversal of 21111202011021 is 12011020211112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21111202011021 - 2² = 21111202011017 is a prime.

It is a super-2 number, since 2×21111202011021² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111202011721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20507910 + ... + 21512711.

It is an arithmetic number, because the mean of its divisors is an integer number (1862942255748).

Almost surely, 2^{21111202011021} is an apocalyptic number.

It is an amenable number.

21111202011021 is a deficient number, since it is larger than the sum of its proper divisors (8695874080947).

21111202011021 is a wasteful number, since it uses less digits than its factorization.

21111202011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42030492.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21111202011021 its reverse (12011020211112), we get a palindrome (33122222222133).

The spelling of 21111202011021 in words is "twenty-one trillion, one hundred eleven billion, two hundred two million, eleven thousand, twenty-one".