20488561 has 8 divisors (see below), whose sum is σ = 21901824. Its totient is φ = 19118880.

The previous prime is 20488537. The next prime is 20488579. The reversal of 20488561 is 16588402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20488561 - 2¹⁷ = 20357489 is a prime.

It is a super-2 number, since 2×20488561² = 839562263701442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20480561) 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 7 ways as a sum of consecutive naturals, for example, 9921 + ... + 11806.

It is an arithmetic number, because the mean of its divisors is an integer number (2737728).

Almost surely, 2^20488561 is an apocalyptic number.

It is an amenable number.

20488561 is a deficient number, since it is larger than the sum of its proper divisors (1413263).

20488561 is a wasteful number, since it uses less digits than its factorization.

20488561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21791.

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 20488561 is about 4526.4291665727. The cubic root of 20488561 is about 273.6342688244.

It can be divided in two parts, 2048 and 8561, that added together give a square (10609 = 103²).

The spelling of 20488561 in words is "twenty million, four hundred eighty-eight thousand, five hundred sixty-one".