10421555021 has 2 divisors, whose sum is σ = 10421555022. Its totient is φ = 10421555020.

The previous prime is 10421555003. The next prime is 10421555051. The reversal of 10421555021 is 12055512401.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8772382921 + 1649172100 = 93661^2 + 40610^2 .

It is a cyclic number.

It is not a de Polignac number, because 10421555021 - 2¹⁴ = 10421538637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10421555051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5210777510 + 5210777511.

It is an arithmetic number, because the mean of its divisors is an integer number (5210777511).

Almost surely, 2^10421555021 is an apocalyptic number.

It is an amenable number.

10421555021 is a deficient number, since it is larger than the sum of its proper divisors (1).

10421555021 is an equidigital number, since it uses as much as digits as its factorization.

10421555021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 26.

The spelling of 10421555021 in words is "ten billion, four hundred twenty-one million, five hundred fifty-five thousand, twenty-one".