81770415385 has 8 divisors (see below), whose sum is σ = 101289805056. Its totient is φ = 63306127920.

The previous prime is 81770415383. The next prime is 81770415409. The reversal of 81770415385 is 58351407718.

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

It is not a de Polignac number, because 81770415385 - 2¹ = 81770415383 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81770415383) 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, 263775379 + ... + 263775688.

It is an arithmetic number, because the mean of its divisors is an integer number (12661225632).

Almost surely, 2^81770415385 is an apocalyptic number.

It is an amenable number.

81770415385 is a deficient number, since it is larger than the sum of its proper divisors (19519389671).

81770415385 is a wasteful number, since it uses less digits than its factorization.

81770415385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 527551103.

The product of its (nonzero) digits is 940800, while the sum is 49.

The spelling of 81770415385 in words is "eighty-one billion, seven hundred seventy million, four hundred fifteen thousand, three hundred eighty-five".