161236903 has 4 divisors (see below), whose sum is σ = 161389648. Its totient is φ = 161084160.

The previous prime is 161236853. The next prime is 161236913. The reversal of 161236903 is 309632161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161236903 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161236913) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74778 + ... + 76903.

It is an arithmetic number, because the mean of its divisors is an integer number (40347412).

Almost surely, 2^161236903 is an apocalyptic number.

161236903 is a deficient number, since it is larger than the sum of its proper divisors (152745).

161236903 is a wasteful number, since it uses less digits than its factorization.

161236903 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152744.

The product of its (nonzero) digits is 5832, while the sum is 31.

The square root of 161236903 is about 12697.9093948571. The cubic root of 161236903 is about 544.2788801755.

The spelling of 161236903 in words is "one hundred sixty-one million, two hundred thirty-six thousand, nine hundred three".