1451721355891 has 2 divisors, whose sum is σ = 1451721355892. Its totient is φ = 1451721355890.

The previous prime is 1451721355873. The next prime is 1451721355897. The reversal of 1451721355891 is 1985531271541.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1451721355891 - 2¹⁵ = 1451721323123 is a prime.

It is not a weakly prime, because it can be changed into another prime (1451721355897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 725860677945 + 725860677946.

It is an arithmetic number, because the mean of its divisors is an integer number (725860677946).

Almost surely, 2^{1451721355891} is an apocalyptic number.

1451721355891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1451721355891 is an equidigital number, since it uses as much as digits as its factorization.

1451721355891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1512000, while the sum is 52.

The spelling of 1451721355891 in words is "one trillion, four hundred fifty-one billion, seven hundred twenty-one million, three hundred fifty-five thousand, eight hundred ninety-one".