18761481 has 6 divisors (see below), whose sum is σ = 27099930. Its totient is φ = 12507648.

The previous prime is 18761461. The next prime is 18761513. The reversal of 18761481 is 18416781.

It can be written as a sum of positive squares in only one way, i.e., 17640000 + 1121481 = 4200^2 + 1059^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18761481 is a prime.

It is a super-2 number, since 2×18761481² = 703986338626722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18761441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1042296 + ... + 1042313.

It is an arithmetic number, because the mean of its divisors is an integer number (4516655).

Almost surely, 2^18761481 is an apocalyptic number.

It is an amenable number.

18761481 is a deficient number, since it is larger than the sum of its proper divisors (8338449).

18761481 is a wasteful number, since it uses less digits than its factorization.

18761481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2084615 (or 2084612 counting only the distinct ones).

The product of its digits is 10752, while the sum is 36.

The square root of 18761481 is about 4331.4525277325. The cubic root of 18761481 is about 265.7188551565.

The spelling of 18761481 in words is "eighteen million, seven hundred sixty-one thousand, four hundred eighty-one".