21010031111111 has 16 divisors (see below), whose sum is σ = 24813136347648. Its totient is φ = 17415637092000.

The previous prime is 21010031111107. The next prime is 21010031111117. The reversal of 21010031111111 is 11111113001012.

It is not a de Polignac number, because 21010031111111 - 2² = 21010031111107 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010031111117) 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, 345517955 + ... + 345578756.

It is an arithmetic number, because the mean of its divisors is an integer number (1550821021728).

Almost surely, 2^{21010031111111} is an apocalyptic number.

21010031111111 is a deficient number, since it is larger than the sum of its proper divisors (3803105236537).

21010031111111 is a wasteful number, since it uses less digits than its factorization.

21010031111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 691096862.

The product of its (nonzero) digits is 6, while the sum is 14.

Adding to 21010031111111 its reverse (11111113001012), we get a palindrome (32121144112123).

The spelling of 21010031111111 in words is "twenty-one trillion, ten billion, thirty-one million, one hundred eleven thousand, one hundred eleven".