81849937305511 has 4 divisors (see below), whose sum is σ = 81851453071024. Its totient is φ = 81848421540000.

The previous prime is 81849937305491. The next prime is 81849937305541. The reversal of 81849937305511 is 11550373994818.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81849937305511 - 2²⁵ = 81849903751079 is a prime.

It is a super-2 number, since 2×81849937305511² (a number of 29 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 (81849937305541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 757801755 + ... + 757909756.

It is an arithmetic number, because the mean of its divisors is an integer number (20462863267756).

Almost surely, 2^{81849937305511} is an apocalyptic number.

81849937305511 is a deficient number, since it is larger than the sum of its proper divisors (1515765513).

81849937305511 is a wasteful number, since it uses less digits than its factorization.

81849937305511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1515765512.

The product of its (nonzero) digits is 32659200, while the sum is 64.

The spelling of 81849937305511 in words is "eighty-one trillion, eight hundred forty-nine billion, nine hundred thirty-seven million, three hundred five thousand, five hundred eleven".