10821577421 has 2 divisors, whose sum is σ = 10821577422. Its totient is φ = 10821577420.

The previous prime is 10821577399. The next prime is 10821577457. The reversal of 10821577421 is 12477512801.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10772156521 + 49420900 = 103789^2 + 7030^2 .

It is a cyclic number.

It is not a de Polignac number, because 10821577421 - 2¹⁸ = 10821315277 is a prime.

It is a super-2 number, since 2×10821577421² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10821877421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5410788710 + 5410788711.

It is an arithmetic number, because the mean of its divisors is an integer number (5410788711).

Almost surely, 2^10821577421 is an apocalyptic number.

It is an amenable number.

10821577421 is a deficient number, since it is larger than the sum of its proper divisors (1).

10821577421 is an equidigital number, since it uses as much as digits as its factorization.

10821577421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31360, while the sum is 38.

The spelling of 10821577421 in words is "ten billion, eight hundred twenty-one million, five hundred seventy-seven thousand, four hundred twenty-one".