20403145 has 32 divisors (see below), whose sum is σ = 30233088. Its totient is φ = 12899328.

The previous prime is 20403137. The next prime is 20403151. The reversal of 20403145 is 54130402.

It is not a de Polignac number, because 20403145 - 2³ = 20403137 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31212 + ... + 31858.

It is an arithmetic number, because the mean of its divisors is an integer number (944784).

Almost surely, 2^20403145 is an apocalyptic number.

It is an amenable number.

20403145 is a deficient number, since it is larger than the sum of its proper divisors (9829943).

20403145 is a wasteful number, since it uses less digits than its factorization.

20403145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 20403145 is about 4516.9840601888. The cubic root of 20403145 is about 273.2534823592.

Adding to 20403145 its reverse (54130402), we get a palindrome (74533547).

The spelling of 20403145 in words is "twenty million, four hundred three thousand, one hundred forty-five".