20229551 has 4 divisors (see below), whose sum is σ = 20238552. Its totient is φ = 20220552.

The previous prime is 20229529. The next prime is 20229553. The reversal of 20229551 is 15592202.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 15592202 = 2 ⋅7796101.

It is a cyclic number.

It is not a de Polignac number, because 20229551 - 2⁶ = 20229487 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20229551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20229553) 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, 2036 + ... + 6678.

It is an arithmetic number, because the mean of its divisors is an integer number (5059638).

Almost surely, 2^20229551 is an apocalyptic number.

20229551 is a deficient number, since it is larger than the sum of its proper divisors (9001).

20229551 is an equidigital number, since it uses as much as digits as its factorization.

20229551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9000.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 20229551 is about 4497.7273149892. The cubic root of 20229551 is about 272.4763091376.

The spelling of 20229551 in words is "twenty million, two hundred twenty-nine thousand, five hundred fifty-one".