65544725531021 has 16 divisors (see below), whose sum is σ = 71518188461760. Its totient is φ = 59573739189120.

The previous prime is 65544725530913. The next prime is 65544725531039. The reversal of 65544725531021 is 12013552744556.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65544725531021 is a prime.

It is a super-2 number, since 2×65544725531021² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65544725531221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1683939266 + ... + 1683978188.

It is an arithmetic number, because the mean of its divisors is an integer number (4469886778860).

Almost surely, 2^{65544725531021} is an apocalyptic number.

It is an amenable number.

65544725531021 is a deficient number, since it is larger than the sum of its proper divisors (5973462930739).

65544725531021 is a wasteful number, since it uses less digits than its factorization.

65544725531021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66796.

The product of its (nonzero) digits is 5040000, while the sum is 50.

The spelling of 65544725531021 in words is "sixty-five trillion, five hundred forty-four billion, seven hundred twenty-five million, five hundred thirty-one thousand, twenty-one".