20616949 has 4 divisors (see below), whose sum is σ = 20633260. Its totient is φ = 20600640.

The previous prime is 20616931. The next prime is 20616961. The reversal of 20616949 is 94961602.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13950225 + 6666724 = 3735^2 + 2582^2 .

It is a cyclic number.

It is not a de Polignac number, because 20616949 - 2¹⁷ = 20485877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20616979) 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, 6084 + ... + 8845.

It is an arithmetic number, because the mean of its divisors is an integer number (5158315).

Almost surely, 2^20616949 is an apocalyptic number.

It is an amenable number.

20616949 is a deficient number, since it is larger than the sum of its proper divisors (16311).

20616949 is a wasteful number, since it uses less digits than its factorization.

20616949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16310.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 20616949 is about 4540.5890587015. The cubic root of 20616949 is about 274.2046396018.

The spelling of 20616949 in words is "twenty million, six hundred sixteen thousand, nine hundred forty-nine".