21101103031 has 4 divisors (see below), whose sum is σ = 21355333272. Its totient is φ = 20846872792.

The previous prime is 21101103029. The next prime is 21101103043. The reversal of 21101103031 is 13030110112.

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 21101103031 - 2¹ = 21101103029 is a prime.

It is a super-2 number, since 2×21101103031² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101103631) 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, 127114996 + ... + 127115161.

It is an arithmetic number, because the mean of its divisors is an integer number (5338833318).

Almost surely, 2^21101103031 is an apocalyptic number.

21101103031 is a deficient number, since it is larger than the sum of its proper divisors (254230241).

21101103031 is an equidigital number, since it uses as much as digits as its factorization.

21101103031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254230240.

The product of its (nonzero) digits is 18, while the sum is 13.

Adding to 21101103031 its reverse (13030110112), we get a palindrome (34131213143).

The spelling of 21101103031 in words is "twenty-one billion, one hundred one million, one hundred three thousand, thirty-one".