1031210000021 has 2 divisors, whose sum is σ = 1031210000022. Its totient is φ = 1031210000020.

The previous prime is 1031209999951. The next prime is 1031210000033. The reversal of 1031210000021 is 1200000121301.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 703065480100 + 328144519921 = 838490^2 + 572839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1031210000021 - 2²² = 1031205805717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1031209999957 and 1031210000011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1031210020021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 515605000010 + 515605000011.

It is an arithmetic number, because the mean of its divisors is an integer number (515605000011).

Almost surely, 2^{1031210000021} is an apocalyptic number.

It is an amenable number.

1031210000021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1031210000021 is an equidigital number, since it uses as much as digits as its factorization.

1031210000021 is an evil number, because the sum of its binary digits is even.

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

Adding to 1031210000021 its reverse (1200000121301), we get a palindrome (2231210121322).

The spelling of 1031210000021 in words is "one trillion, thirty-one billion, two hundred ten million, twenty-one", and thus it is an aban number.