18460661478 has 64 divisors (see below), whose sum is σ = 44494717440. Its totient is φ = 4988086272.

The previous prime is 18460661477. The next prime is 18460661537. The reversal of 18460661478 is 87416606481.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18460661478.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18460661477) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 440400 + ... + 480492.

It is an arithmetic number, because the mean of its divisors is an integer number (695229960).

Almost surely, 2^18460661478 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18460661478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22247358720).

18460661478 is an abundant number, since it is smaller than the sum of its proper divisors (26034055962).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18460661478 is a wasteful number, since it uses less digits than its factorization.

18460661478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40701.

The product of its (nonzero) digits is 1548288, while the sum is 51.

The spelling of 18460661478 in words is "eighteen billion, four hundred sixty million, six hundred sixty-one thousand, four hundred seventy-eight".