21120261552 has 120 divisors (see below), whose sum is σ = 64010746800. Its totient is φ = 6462134784.

The previous prime is 21120261527. The next prime is 21120261577. The reversal of 21120261552 is 25516202112.

21120261552 is a `hidden beast` number, since 21 + 1 + 20 + 2 + 615 + 5 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (21120261527) and next prime (21120261577).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 303574 + ... + 366602.

It is an arithmetic number, because the mean of its divisors is an integer number (533422890).

Almost surely, 2^21120261552 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 21120261552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32005373400).

21120261552 is an abundant number, since it is smaller than the sum of its proper divisors (42890485248).

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

21120261552 is a wasteful number, since it uses less digits than its factorization.

21120261552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63235 (or 63226 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 21120261552 its reverse (25516202112), we get a palindrome (46636463664).

The spelling of 21120261552 in words is "twenty-one billion, one hundred twenty million, two hundred sixty-one thousand, five hundred fifty-two".