20409554 has 40 divisors (see below), whose sum is σ = 36526140. Its totient is φ = 8518400.

The previous prime is 20409547. The next prime is 20409583. The reversal of 20409554 is 45590402.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20043529 + 366025 = 4477^2 + 605^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 497774 + ... + 497814.

Almost surely, 2^20409554 is an apocalyptic number.

20409554 is a deficient number, since it is larger than the sum of its proper divisors (16116586).

20409554 is an equidigital number, since it uses as much as digits as its factorization.

20409554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 20409554 is about 4517.6934380279. The cubic root of 20409554 is about 273.2820906650.

Adding to 20409554 its reverse (45590402), we get a palindrome (65999956).

The spelling of 20409554 in words is "twenty million, four hundred nine thousand, five hundred fifty-four".