1818921451 has 2 divisors, whose sum is σ = 1818921452. Its totient is φ = 1818921450.

The previous prime is 1818921421. The next prime is 1818921487. The reversal of 1818921451 is 1541298181.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1818921451 - 2⁷ = 1818921323 is a prime.

It is not a weakly prime, because it can be changed into another prime (1818921421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 909460725 + 909460726.

It is an arithmetic number, because the mean of its divisors is an integer number (909460726).

Almost surely, 2^1818921451 is an apocalyptic number.

1818921451 is a deficient number, since it is larger than the sum of its proper divisors (1).

1818921451 is an equidigital number, since it uses as much as digits as its factorization.

1818921451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23040, while the sum is 40.

The square root of 1818921451 is about 42648.8153528325. The cubic root of 1818921451 is about 1220.6879240835.

The spelling of 1818921451 in words is "one billion, eight hundred eighteen million, nine hundred twenty-one thousand, four hundred fifty-one".