21011649120 has 1152 divisors, whose sum is σ = 96598075392. Its totient is φ = 4025548800.

The previous prime is 21011649119. The next prime is 21011649143. The reversal of 21011649120 is 2194611012.

21011649120 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 1 + 649 + 12 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 133832082 + ... + 133832238.

It is an arithmetic number, because the mean of its divisors is an integer number (83852496).

Almost surely, 2^21011649120 is an apocalyptic number.

21011649120 is a gapful number since it is divisible by the number (20) 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 21011649120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48299037696).

21011649120 is an abundant number, since it is smaller than the sum of its proper divisors (75586426272).

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

21011649120 is a wasteful number, since it uses less digits than its factorization.

21011649120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The spelling of 21011649120 in words is "twenty-one billion, eleven million, six hundred forty-nine thousand, one hundred twenty".