27121155516 has 144 divisors (see below), whose sum is σ = 84707872704. Its totient is φ = 7124779008.

The previous prime is 27121155469. The next prime is 27121155517. The reversal of 27121155516 is 61555112172.

27121155516 is a `hidden beast` number, since 2 + 7 + 121 + 15 + 5 + 516 = 666.

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 (27121155517) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 825826 + ... + 858038.

It is an arithmetic number, because the mean of its divisors is an integer number (588249116).

Almost surely, 2^27121155516 is an apocalyptic number.

27121155516 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 27121155516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42353936352).

27121155516 is an abundant number, since it is smaller than the sum of its proper divisors (57586717188).

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

27121155516 is a wasteful number, since it uses less digits than its factorization.

27121155516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32500 (or 32495 counting only the distinct ones).

The product of its digits is 21000, while the sum is 36.

Adding to 27121155516 its reverse (61555112172), we get a palindrome (88676267688).

The spelling of 27121155516 in words is "twenty-seven billion, one hundred twenty-one million, one hundred fifty-five thousand, five hundred sixteen".