21030131111 has 4 divisors (see below), whose sum is σ = 22941961224. Its totient is φ = 19118301000.

The previous prime is 21030131071. The next prime is 21030131113. The reversal of 21030131111 is 11113103012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21030131111 - 2⁶ = 21030131047 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 (21030131113) 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, 955915040 + ... + 955915061.

It is an arithmetic number, because the mean of its divisors is an integer number (5735490306).

Almost surely, 2^21030131111 is an apocalyptic number.

21030131111 is a deficient number, since it is larger than the sum of its proper divisors (1911830113).

21030131111 is a wasteful number, since it uses less digits than its factorization.

21030131111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1911830112.

The product of its (nonzero) digits is 18, while the sum is 14.

Adding to 21030131111 its reverse (11113103012), we get a palindrome (32143234123).

The spelling of 21030131111 in words is "twenty-one billion, thirty million, one hundred thirty-one thousand, one hundred eleven".