21404535012 has 192 divisors, whose sum is σ = 65685903360. Its totient is φ = 5900646528.

The previous prime is 21404534993. The next prime is 21404535013. The reversal of 21404535012 is 21053540412.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21404535013) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2694198 + ... + 2702130.

It is an arithmetic number, because the mean of its divisors is an integer number (342114080).

Almost surely, 2^21404535012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21404535012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32842951680).

21404535012 is an abundant number, since it is smaller than the sum of its proper divisors (44281368348).

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

21404535012 is a wasteful number, since it uses less digits than its factorization.

21404535012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8079 (or 8071 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The spelling of 21404535012 in words is "twenty-one billion, four hundred four million, five hundred thirty-five thousand, twelve".