61641521727525 has 108 divisors (see below), whose sum is σ = 118601165205900. Its totient is φ = 30593964994560.

The previous prime is 61641521727521. The next prime is 61641521727553. The reversal of 61641521727525 is 52572712514616.

61641521727525 is a `hidden beast` number, since 6 + 1 + 6 + 41 + 5 + 2 + 1 + 72 + 7 + 525 = 666.

It can be written as a sum of positive squares in 18 ways, for example, as 28269202300641 + 33372319426884 = 5316879^2 + 5776878^2 .

It is not a de Polignac number, because 61641521727525 - 2² = 61641521727521 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61641521727521) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 461571 + ... + 11112879.

Almost surely, 2^{61641521727525} is an apocalyptic number.

It is an amenable number.

61641521727525 is a deficient number, since it is larger than the sum of its proper divisors (56959643478375).

61641521727525 is a wasteful number, since it uses less digits than its factorization.

61641521727525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10651448 (or 10651423 counting only the distinct ones).

The product of its digits is 7056000, while the sum is 54.

The spelling of 61641521727525 in words is "sixty-one trillion, six hundred forty-one billion, five hundred twenty-one million, seven hundred twenty-seven thousand, five hundred twenty-five".