221000403412421 has 2 divisors, whose sum is σ = 221000403412422. Its totient is φ = 221000403412420.

The previous prime is 221000403412379. The next prime is 221000403412441. The reversal of 221000403412421 is 124214304000122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128759265561796 + 92241137850625 = 11347214^2 + 9604225^2 .

It is a cyclic number.

It is not a de Polignac number, because 221000403412421 - 2¹⁰ = 221000403411397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221000403412441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110500201706210 + 110500201706211.

It is an arithmetic number, because the mean of its divisors is an integer number (110500201706211).

Almost surely, 2^{221000403412421} is an apocalyptic number.

It is an amenable number.

221000403412421 is a deficient number, since it is larger than the sum of its proper divisors (1).

221000403412421 is an equidigital number, since it uses as much as digits as its factorization.

221000403412421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3072, while the sum is 26.

Adding to 221000403412421 its reverse (124214304000122), we get a palindrome (345214707412543).

The spelling of 221000403412421 in words is "two hundred twenty-one trillion, four hundred three million, four hundred twelve thousand, four hundred twenty-one".