75771053487649 has 27 divisors (see below), whose sum is σ = 84330050181867. Its totient is φ = 68048412367104.

The previous prime is 75771053487643. The next prime is 75771053487713. The reversal of 75771053487649 is 94678435017757.

It is a happy number.

The square root of 75771053487649 is 8704657.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 62341525792225 + 13429527695424 = 7895665^2 + 3664632^2 .

It is not a de Polignac number, because 75771053487649 - 2²³ = 75771045099041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (75771053487643) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4186930969 + ... + 4186949065.

It is an arithmetic number, because the mean of its divisors is an integer number (3123335191921).

Almost surely, 2^{75771053487649} is an apocalyptic number.

75771053487649 is the 8704657-th square number.

75771053487649 is the 4352329-th centered octagonal number.

It is an amenable number.

75771053487649 is a deficient number, since it is larger than the sum of its proper divisors (8558996694218).

75771053487649 is an frugal number, since it uses more digits than its factorization.

75771053487649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36294 (or 18147 counting only the distinct ones).

The product of its (nonzero) digits is 1244678400, while the sum is 73.

The spelling of 75771053487649 in words is "seventy-five trillion, seven hundred seventy-one billion, fifty-three million, four hundred eighty-seven thousand, six hundred forty-nine".