20226661 has 24 divisors (see below), whose sum is σ = 25654104. Its totient is φ = 15805440.

The previous prime is 20226649. The next prime is 20226673. The reversal of 20226661 is 16662202.

It is an interprime number because it is at equal distance from previous prime (20226649) and next prime (20226673).

It can be written as a sum of positive squares in 4 ways, for example, as 30625 + 20196036 = 175^2 + 4494^2 .

It is not a de Polignac number, because 20226661 - 2⁵ = 20226629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20226631) 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 23 ways as a sum of consecutive naturals, for example, 71841 + ... + 72121.

It is an arithmetic number, because the mean of its divisors is an integer number (1068921).

Almost surely, 2^20226661 is an apocalyptic number.

It is an amenable number.

20226661 is a deficient number, since it is larger than the sum of its proper divisors (5427443).

20226661 is a wasteful number, since it uses less digits than its factorization.

20226661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421 (or 414 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 20226661 is about 4497.4060301467. The cubic root of 20226661 is about 272.4633331693.

Adding to 20226661 its reverse (16662202), we get a palindrome (36888863).

The spelling of 20226661 in words is "twenty million, two hundred twenty-six thousand, six hundred sixty-one".