21061716060 has 240 divisors, whose sum is σ = 75057478272. Its totient is φ = 4376131200.

The previous prime is 21061716047. The next prime is 21061716061. The reversal of 21061716060 is 6061716012.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21061716061) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1578015 + ... + 1591305.

Almost surely, 2^21061716060 is an apocalyptic number.

21061716060 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 21061716060, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37528739136).

21061716060 is an abundant number, since it is smaller than the sum of its proper divisors (53995762212).

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

21061716060 is a wasteful number, since it uses less digits than its factorization.

21061716060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13342 (or 13319 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 30.

The spelling of 21061716060 in words is "twenty-one billion, sixty-one million, seven hundred sixteen thousand, sixty".