1666776040451 has 4 divisors (see below), whose sum is σ = 1676756735472. Its totient is φ = 1656795345432.

The previous prime is 1666776040381. The next prime is 1666776040507. The reversal of 1666776040451 is 1540406776661.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1666776040451 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1666776040393 and 1666776040402.

It is not an unprimeable number, because it can be changed into a prime (1666776046451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4990347260 + ... + 4990347593.

It is an arithmetic number, because the mean of its divisors is an integer number (419189183868).

Almost surely, 2^{1666776040451} is an apocalyptic number.

1666776040451 is a deficient number, since it is larger than the sum of its proper divisors (9980695021).

1666776040451 is an equidigital number, since it uses as much as digits as its factorization.

1666776040451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9980695020.

The product of its (nonzero) digits is 5080320, while the sum is 53.

The spelling of 1666776040451 in words is "one trillion, six hundred sixty-six billion, seven hundred seventy-six million, forty thousand, four hundred fifty-one".