21733961820 has 48 divisors (see below), whose sum is σ = 60902016000. Its totient is φ = 5791254336.

The previous prime is 21733961783. The next prime is 21733961827. The reversal of 21733961820 is 2816933712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21733961827) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60820 + ... + 217179.

It is an arithmetic number, because the mean of its divisors is an integer number (1268792000).

Almost surely, 2^21733961820 is an apocalyptic number.

21733961820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21733961820 is an abundant number, since it is smaller than the sum of its proper divisors (39168054180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21733961820 is a wasteful number, since it uses less digits than its factorization.

21733961820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279314 (or 279312 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 42.

The spelling of 21733961820 in words is "twenty-one billion, seven hundred thirty-three million, nine hundred sixty-one thousand, eight hundred twenty".