21038611776 has 504 divisors, whose sum is σ = 72458336160. Its totient is φ = 5339658240.

The previous prime is 21038611757. The next prime is 21038611831. The reversal of 21038611776 is 67711683012.

It is a super-2 number, since 2×21038611776² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 117534055 + ... + 117534233.

It is an arithmetic number, because the mean of its divisors is an integer number (143766540).

Almost surely, 2^21038611776 is an apocalyptic number.

21038611776 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 21038611776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36229168080).

21038611776 is an abundant number, since it is smaller than the sum of its proper divisors (51419724384).

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

21038611776 is a wasteful number, since it uses less digits than its factorization.

21038611776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283 (or 235 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 42.

The spelling of 21038611776 in words is "twenty-one billion, thirty-eight million, six hundred eleven thousand, seven hundred seventy-six".