21120001031 has 2 divisors, whose sum is σ = 21120001032. Its totient is φ = 21120001030.

The previous prime is 21120001003. The next prime is 21120001081. The reversal of 21120001031 is 13010002112.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120001031 is a prime.

It is a super-2 number, since 2×21120001031² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21120001081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560000515 + 10560000516.

It is an arithmetic number, because the mean of its divisors is an integer number (10560000516).

Almost surely, 2^21120001031 is an apocalyptic number.

21120001031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21120001031 is an equidigital number, since it uses as much as digits as its factorization.

21120001031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21120001031 its reverse (13010002112), we get a palindrome (34130003143).

The spelling of 21120001031 in words is "twenty-one billion, one hundred twenty million, one thousand, thirty-one".