31111101101021 has 4 divisors (see below), whose sum is σ = 31158167820444. Its totient is φ = 31064034381600.

The previous prime is 31111101100997. The next prime is 31111101101107. The reversal of 31111101101021 is 12010110111113.

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

It can be written as a sum of positive squares in 2 ways, for example, as 24300118135225 + 6810982965796 = 4929515^2 + 2609786^2 .

It is a cyclic number.

It is not a de Polignac number, because 31111101101021 - 2¹⁸ = 31111100838877 is a prime.

It is a super-2 number, since 2×31111101101021² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31111101100987 and 31111101101005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31111101101321) 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, 23533358720 + ... + 23533360041.

It is an arithmetic number, because the mean of its divisors is an integer number (7789541955111).

Almost surely, 2^{31111101101021} is an apocalyptic number.

It is an amenable number.

31111101101021 is a deficient number, since it is larger than the sum of its proper divisors (47066719423).

31111101101021 is an equidigital number, since it uses as much as digits as its factorization.

31111101101021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47066719422.

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

Adding to 31111101101021 its reverse (12010110111113), we get a palindrome (43121211212134).

The spelling of 31111101101021 in words is "thirty-one trillion, one hundred eleven billion, one hundred one million, one hundred one thousand, twenty-one".