21125526077 has 8 divisors (see below), whose sum is σ = 21240156600. Its totient is φ = 21011203584.

The previous prime is 21125526047. The next prime is 21125526089. The reversal of 21125526077 is 77062552112.

It can be written as a sum of positive squares in 4 ways, for example, as 625300036 + 20500226041 = 25006^2 + 143179^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21125526077 - 2¹⁰ = 21125525053 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21125526077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21125526047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61199 + ... + 214467.

It is an arithmetic number, because the mean of its divisors is an integer number (2655019575).

Almost surely, 2^21125526077 is an apocalyptic number.

It is an amenable number.

21125526077 is a deficient number, since it is larger than the sum of its proper divisors (114630523).

21125526077 is a wasteful number, since it uses less digits than its factorization.

21125526077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154015.

The product of its (nonzero) digits is 58800, while the sum is 38.

The spelling of 21125526077 in words is "twenty-one billion, one hundred twenty-five million, five hundred twenty-six thousand, seventy-seven".