2721551616 has 144 divisors (see below), whose sum is σ = 9198000000. Its totient is φ = 777572352.

The previous prime is 2721551611. The next prime is 2721551627. The reversal of 2721551616 is 6161551272.

2721551616 is a `hidden beast` number, since 27 + 2 + 15 + 5 + 1 + 616 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×2721551616² = 14813686397104422912, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2721551611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20260 + ... + 76508.

It is an arithmetic number, because the mean of its divisors is an integer number (63875000).

Almost surely, 2^2721551616 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 2721551616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4599000000).

2721551616 is an abundant number, since it is smaller than the sum of its proper divisors (6476448384).

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

2721551616 is an equidigital number, since it uses as much as digits as its factorization.

2721551616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56281 (or 56261 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 2721551616 is about 52168.4925601651. The cubic root of 2721551616 is about 1396.1717891617.

The spelling of 2721551616 in words is "two billion, seven hundred twenty-one million, five hundred fifty-one thousand, six hundred sixteen".