1021312421 has 2 divisors, whose sum is σ = 1021312422. Its totient is φ = 1021312420.

The previous prime is 1021312399. The next prime is 1021312433. The reversal of 1021312421 is 1242131201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 527850625 + 493461796 = 22975^2 + 22214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021312421 is a prime.

It is a super-2 number, since 2×1021312421² = 2086158122577762482, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1021312421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021312471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510656210 + 510656211.

It is an arithmetic number, because the mean of its divisors is an integer number (510656211).

Almost surely, 2^1021312421 is an apocalyptic number.

It is an amenable number.

1021312421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021312421 is an equidigital number, since it uses as much as digits as its factorization.

1021312421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1021312421 is about 31957.9789880399. The cubic root of 1021312421 is about 1007.0542607262.

Adding to 1021312421 its reverse (1242131201), we get a palindrome (2263443622).

The spelling of 1021312421 in words is "one billion, twenty-one million, three hundred twelve thousand, four hundred twenty-one".