1681420051 has 2 divisors, whose sum is σ = 1681420052. Its totient is φ = 1681420050.

The previous prime is 1681419979. The next prime is 1681420061. The reversal of 1681420051 is 1500241861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1681420051 - 2⁹ = 1681419539 is a prime.

It is not a weakly prime, because it can be changed into another prime (1681420061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840710025 + 840710026.

It is an arithmetic number, because the mean of its divisors is an integer number (840710026).

Almost surely, 2^1681420051 is an apocalyptic number.

1681420051 is a deficient number, since it is larger than the sum of its proper divisors (1).

1681420051 is an equidigital number, since it uses as much as digits as its factorization.

1681420051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 1681420051 is about 41005.1222532015. The cubic root of 1681420051 is about 1189.1192435375.

The spelling of 1681420051 in words is "one billion, six hundred eighty-one million, four hundred twenty thousand, fifty-one".