18161335696 has 45 divisors (see below), whose sum is σ = 40941006561. Its totient is φ = 7781812416.

The previous prime is 18161335681. The next prime is 18161335757. The reversal of 18161335696 is 69653316181.

The square root of 18161335696 is 134764.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 13600224400 + 4561111296 = 116620^2 + 67536^2 .

It is a super-2 number, since 2×18161335696² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3770986 + ... + 3775798.

Almost surely, 2^18161335696 is an apocalyptic number.

18161335696 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

18161335696 is the 134764-th square number.

It is an amenable number.

18161335696 is an abundant number, since it is smaller than the sum of its proper divisors (22779670865).

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

18161335696 is an frugal number, since it uses more digits than its factorization.

18161335696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9648 (or 4822 counting only the distinct ones).

The product of its digits is 699840, while the sum is 49.

Multiplying 18161335696 by its sum of digits (49), we get a square (889905449104 = 943348²).

18161335696 divided by its sum of digits (49) gives a square (370639504 = 19252²).

The spelling of 18161335696 in words is "eighteen billion, one hundred sixty-one million, three hundred thirty-five thousand, six hundred ninety-six".