2151466403665 has 4 divisors (see below), whose sum is σ = 2581759684404. Its totient is φ = 1721173122928.

The previous prime is 2151466403609. The next prime is 2151466403693. The reversal of 2151466403665 is 5663046641512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1603280166849 + 548186236816 = 1266207^2 + 740396^2 .

It is a cyclic number.

It is not a de Polignac number, because 2151466403665 - 2⁹ = 2151466403153 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215146640362 + ... + 215146640371.

It is an arithmetic number, because the mean of its divisors is an integer number (645439921101).

Almost surely, 2^{2151466403665} is an apocalyptic number.

It is an amenable number.

2151466403665 is a deficient number, since it is larger than the sum of its proper divisors (430293280739).

2151466403665 is an equidigital number, since it uses as much as digits as its factorization.

2151466403665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430293280738.

The product of its (nonzero) digits is 3110400, while the sum is 49.

The spelling of 2151466403665 in words is "two trillion, one hundred fifty-one billion, four hundred sixty-six million, four hundred three thousand, six hundred sixty-five".