61221027552 has 96 divisors (see below), whose sum is σ = 162381542400. Its totient is φ = 20194556928.

The previous prime is 61221027523. The next prime is 61221027559. The reversal of 61221027552 is 25572012216.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×61221027552² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61221027559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11594449 + ... + 11599727.

It is an arithmetic number, because the mean of its divisors is an integer number (1691474400).

Almost surely, 2^61221027552 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 61221027552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81190771200).

61221027552 is an abundant number, since it is smaller than the sum of its proper divisors (101160514848).

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

61221027552 is a wasteful number, since it uses less digits than its factorization.

61221027552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6528 (or 6520 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 33.

Adding to 61221027552 its reverse (25572012216), we get a palindrome (86793039768).

The spelling of 61221027552 in words is "sixty-one billion, two hundred twenty-one million, twenty-seven thousand, five hundred fifty-two".