21766034661 has 32 divisors (see below), whose sum is σ = 34033536000. Its totient is φ = 12368144880.

The previous prime is 21766034627. The next prime is 21766034669. The reversal of 21766034661 is 16643066712.

It is not a de Polignac number, because 21766034661 - 2¹⁹ = 21765510373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21766034669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 125106 + ... + 243276.

It is an arithmetic number, because the mean of its divisors is an integer number (1063548000).

Almost surely, 2^21766034661 is an apocalyptic number.

21766034661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21766034661 is a deficient number, since it is larger than the sum of its proper divisors (12267501339).

21766034661 is a wasteful number, since it uses less digits than its factorization.

21766034661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118374 (or 118360 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 42.

The spelling of 21766034661 in words is "twenty-one billion, seven hundred sixty-six million, thirty-four thousand, six hundred sixty-one".