20415144 has 16 divisors (see below), whose sum is σ = 51037920. Its totient is φ = 6805040.

The previous prime is 20415133. The next prime is 20415149. The reversal of 20415144 is 44151402.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20415144.

It is not an unprimeable number, because it can be changed into a prime (20415149) 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, 425292 + ... + 425339.

It is an arithmetic number, because the mean of its divisors is an integer number (3189870).

Almost surely, 2^20415144 is an apocalyptic number.

20415144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20415144 is an abundant number, since it is smaller than the sum of its proper divisors (30622776).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20415144 is a wasteful number, since it uses less digits than its factorization.

20415144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 850640 (or 850636 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 20415144 is about 4518.3120742153. The cubic root of 20415144 is about 273.3070382531.

Adding to 20415144 its reverse (44151402), we get a palindrome (64566546).

The spelling of 20415144 in words is "twenty million, four hundred fifteen thousand, one hundred forty-four".