18281502077 has 4 divisors (see below), whose sum is σ = 18414943836. Its totient is φ = 18148060320.

The previous prime is 18281502017. The next prime is 18281502079. The reversal of 18281502077 is 77020518281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77020518281 = 7 ⋅11002931183.

It can be written as a sum of positive squares in 2 ways, for example, as 11006947396 + 7274554681 = 104914^2 + 85291^2 .

It is a cyclic number.

It is not a de Polignac number, because 18281502077 - 2³⁴ = 1101632893 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 (18281502079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66720674 + ... + 66720947.

It is an arithmetic number, because the mean of its divisors is an integer number (4603735959).

Almost surely, 2^18281502077 is an apocalyptic number.

It is an amenable number.

18281502077 is a deficient number, since it is larger than the sum of its proper divisors (133441759).

18281502077 is a wasteful number, since it uses less digits than its factorization.

18281502077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133441758.

The product of its (nonzero) digits is 62720, while the sum is 41.

The spelling of 18281502077 in words is "eighteen billion, two hundred eighty-one million, five hundred two thousand, seventy-seven".