81745290879 has 16 divisors (see below), whose sum is σ = 124568533248. Its totient is φ = 46709989632.

The previous prime is 81745290871. The next prime is 81745290881. The reversal of 81745290879 is 97809254718.

It is not a de Polignac number, because 81745290879 - 2³ = 81745290871 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81745290871) 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, 853039 + ... + 944015.

It is an arithmetic number, because the mean of its divisors is an integer number (7785533328).

Almost surely, 2^81745290879 is an apocalyptic number.

81745290879 is a deficient number, since it is larger than the sum of its proper divisors (42823242369).

81745290879 is a wasteful number, since it uses less digits than its factorization.

81745290879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133774.

The product of its (nonzero) digits is 10160640, while the sum is 60.

The spelling of 81745290879 in words is "eighty-one billion, seven hundred forty-five million, two hundred ninety thousand, eight hundred seventy-nine".