20611357 has 4 divisors (see below), whose sum is σ = 22196860. Its totient is φ = 19025856.

The previous prime is 20611343. The next prime is 20611369. The reversal of 20611357 is 75311602.

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 2752281 + 17859076 = 1659^2 + 4226^2 .

It is a cyclic number.

It is not a de Polignac number, because 20611357 - 2¹⁵ = 20578589 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 (20611057) 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, 792732 + ... + 792757.

It is an arithmetic number, because the mean of its divisors is an integer number (5549215).

Almost surely, 2^20611357 is an apocalyptic number.

It is an amenable number.

20611357 is a deficient number, since it is larger than the sum of its proper divisors (1585503).

20611357 is a wasteful number, since it uses less digits than its factorization.

20611357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1585502.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 20611357 is about 4539.9732378066. The cubic root of 20611357 is about 274.1798462308.

Adding to 20611357 its reverse (75311602), we get a palindrome (95922959).

The spelling of 20611357 in words is "twenty million, six hundred eleven thousand, three hundred fifty-seven".