18954961 has 4 divisors (see below), whose sum is σ = 19214692. Its totient is φ = 18695232.

The previous prime is 18954917. The next prime is 18954979. The reversal of 18954961 is 16945981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16945981 = 13 ⋅1303537.

It can be written as a sum of positive squares in 2 ways, for example, as 16000000 + 2954961 = 4000^2 + 1719^2 .

It is a cyclic number.

It is not a de Polignac number, because 18954961 - 2¹³ = 18946769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18954911) 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 3 ways as a sum of consecutive naturals, for example, 129756 + ... + 129901.

It is an arithmetic number, because the mean of its divisors is an integer number (4803673).

Almost surely, 2^18954961 is an apocalyptic number.

It is an amenable number.

18954961 is a deficient number, since it is larger than the sum of its proper divisors (259731).

18954961 is an equidigital number, since it uses as much as digits as its factorization.

18954961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259730.

The product of its digits is 77760, while the sum is 43.

The square root of 18954961 is about 4353.7295506267. The cubic root of 18954961 is about 266.6291521880.

The spelling of 18954961 in words is "eighteen million, nine hundred fifty-four thousand, nine hundred sixty-one".