18061199477 has 4 divisors (see below), whose sum is σ = 18061473036. Its totient is φ = 18060925920.

The previous prime is 18061199407. The next prime is 18061199503. The reversal of 18061199477 is 77499116081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 77499116081 = 101 ⋅767317981.

It can be written as a sum of positive squares in 2 ways, for example, as 9925339876 + 8135859601 = 99626^2 + 90199^2 .

It is a cyclic number.

It is not a de Polignac number, because 18061199477 - 2¹² = 18061195381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18061199407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30227 + ... + 192447.

It is an arithmetic number, because the mean of its divisors is an integer number (4515368259).

Almost surely, 2^18061199477 is an apocalyptic number.

It is an amenable number.

18061199477 is a deficient number, since it is larger than the sum of its proper divisors (273559).

18061199477 is a wasteful number, since it uses less digits than its factorization.

18061199477 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273558.

The product of its (nonzero) digits is 762048, while the sum is 53.

The spelling of 18061199477 in words is "eighteen billion, sixty-one million, one hundred ninety-nine thousand, four hundred seventy-seven".