55721261000 has 32 divisors (see below), whose sum is σ = 130387753080. Its totient is φ = 22288504000.

The previous prime is 55721260981. The next prime is 55721261017. The reversal of 55721261000 is 16212755.

It can be written as a sum of positive squares in 4 ways, for example, as 18214741444 + 37506519556 = 134962^2 + 193666^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27859631 + ... + 27861630.

Almost surely, 2^55721261000 is an apocalyptic number.

55721261000 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

55721261000 is an abundant number, since it is smaller than the sum of its proper divisors (74666492080).

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

55721261000 is a wasteful number, since it uses less digits than its factorization.

55721261000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55721282 (or 55721268 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 29.

Adding to 55721261000 its reverse (16212755), we get a palindrome (55737473755).

The spelling of 55721261000 in words is "fifty-five billion, seven hundred twenty-one million, two hundred sixty-one thousand".