1366416821 has 24 divisors (see below), whose sum is σ = 1791146112. Its totient is φ = 1018432800.

The previous prime is 1366416773. The next prime is 1366416823. The reversal of 1366416821 is 1286146631.

It is a de Polignac number, because none of the positive numbers 2^k-1366416821 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1366416823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15590 + ... + 54551.

It is an arithmetic number, because the mean of its divisors is an integer number (74631088).

Almost surely, 2^1366416821 is an apocalyptic number.

1366416821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1366416821 is a deficient number, since it is larger than the sum of its proper divisors (424729291).

1366416821 is a wasteful number, since it uses less digits than its factorization.

1366416821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70193 (or 70182 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 1366416821 is about 36965.0756931458. The cubic root of 1366416821 is about 1109.6714177712.

The spelling of 1366416821 in words is "one billion, three hundred sixty-six million, four hundred sixteen thousand, eight hundred twenty-one".