21966779016 has 512 divisors, whose sum is σ = 79833600000. Its totient is φ = 5434490880.

The previous prime is 21966778993. The next prime is 21966779053. The reversal of 21966779016 is 61097766912.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 48923560 + ... + 48924008.

It is an arithmetic number, because the mean of its divisors is an integer number (155925000).

Almost surely, 2^21966779016 is an apocalyptic number.

21966779016 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21966779016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39916800000).

21966779016 is an abundant number, since it is smaller than the sum of its proper divisors (57866820984).

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

21966779016 is a wasteful number, since it uses less digits than its factorization.

21966779016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 634 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 54.

The spelling of 21966779016 in words is "twenty-one billion, nine hundred sixty-six million, seven hundred seventy-nine thousand, sixteen".