1641451421 has 2 divisors, whose sum is σ = 1641451422. Its totient is φ = 1641451420.

The previous prime is 1641451411. The next prime is 1641451429. The reversal of 1641451421 is 1241541461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1569031321 + 72420100 = 39611^2 + 8510^2 .

It is an emirp because it is prime and its reverse (1241541461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1641451421 - 2²⁶ = 1574342557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641451429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820725710 + 820725711.

It is an arithmetic number, because the mean of its divisors is an integer number (820725711).

Almost surely, 2^1641451421 is an apocalyptic number.

It is an amenable number.

1641451421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641451421 is an equidigital number, since it uses as much as digits as its factorization.

1641451421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840, while the sum is 29.

The square root of 1641451421 is about 40514.8296429838. The cubic root of 1641451421 is about 1179.6214961926.

Adding to 1641451421 its reverse (1241541461), we get a palindrome (2882992882).

The spelling of 1641451421 in words is "one billion, six hundred forty-one million, four hundred fifty-one thousand, four hundred twenty-one".