66700090409 has 4 divisors (see below), whose sum is σ = 66700641540. Its totient is φ = 66699539280.

The previous prime is 66700090381. The next prime is 66700090421. The reversal of 66700090409 is 90409000766.

66700090409 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 8177223184 + 58522867225 = 90428^2 + 241915^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66700090409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66700090489) 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, 6374 + ... + 365295.

It is an arithmetic number, because the mean of its divisors is an integer number (16675160385).

Almost surely, 2^66700090409 is an apocalyptic number.

It is an amenable number.

66700090409 is a deficient number, since it is larger than the sum of its proper divisors (551131).

66700090409 is a wasteful number, since it uses less digits than its factorization.

66700090409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551130.

The product of its (nonzero) digits is 81648, while the sum is 41.

The spelling of 66700090409 in words is "sixty-six billion, seven hundred million, ninety thousand, four hundred nine".