29181918193 has 8 divisors (see below), whose sum is σ = 29234113128. Its totient is φ = 29129758464.

The previous prime is 29181918187. The next prime is 29181918203. The reversal of 29181918193 is 39181918192.

It can be written as a sum of positive squares in 4 ways, for example, as 1074725089 + 28107193104 = 32783^2 + 167652^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-29181918193 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 29181918193.

It is not an unprimeable number, because it can be changed into a prime (29181916193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2072505 + ... + 2086537.

It is an arithmetic number, because the mean of its divisors is an integer number (3654264141).

Almost surely, 2^29181918193 is an apocalyptic number.

It is an amenable number.

29181918193 is a deficient number, since it is larger than the sum of its proper divisors (52194935).

29181918193 is a wasteful number, since it uses less digits than its factorization.

29181918193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17603.

The product of its digits is 279936, while the sum is 52.

Subtracting 29181918193 from its reverse (39181918192), we obtain a palindrome (9999999999).

The spelling of 29181918193 in words is "twenty-nine billion, one hundred eighty-one million, nine hundred eighteen thousand, one hundred ninety-three".