181961606 has 4 divisors (see below), whose sum is σ = 272942412. Its totient is φ = 90980802.

The previous prime is 181961543. The next prime is 181961629. The reversal of 181961606 is 606169181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 606169181 = 181 ⋅3349001.

It is a super-2 number, since 2×181961606² = 66220052116198472, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 181961606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45490400 + ... + 45490403.

It is an arithmetic number, because the mean of its divisors is an integer number (68235603).

Almost surely, 2^181961606 is an apocalyptic number.

181961606 is a deficient number, since it is larger than the sum of its proper divisors (90980806).

181961606 is an equidigital number, since it uses as much as digits as its factorization.

181961606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90980805.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 181961606 is about 13489.3145118646. The cubic root of 181961606 is about 566.6652580511.

The spelling of 181961606 in words is "one hundred eighty-one million, nine hundred sixty-one thousand, six hundred six".