1366021909505 has 32 divisors (see below), whose sum is σ = 1866120622848. Its totient is φ = 950213017600.

The previous prime is 1366021909489. The next prime is 1366021909543. The reversal of 1366021909505 is 5059091206631.

It is not a de Polignac number, because 1366021909505 - 2⁴ = 1366021909489 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1366021909505.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27198977 + ... + 27249153.

It is an arithmetic number, because the mean of its divisors is an integer number (58316269464).

Almost surely, 2^{1366021909505} is an apocalyptic number.

It is an amenable number.

1366021909505 is a deficient number, since it is larger than the sum of its proper divisors (500098713343).

1366021909505 is a wasteful number, since it uses less digits than its factorization.

1366021909505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71737.

The product of its (nonzero) digits is 437400, while the sum is 47.

The spelling of 1366021909505 in words is "one trillion, three hundred sixty-six billion, twenty-one million, nine hundred nine thousand, five hundred five".