20493405 has 48 divisors (see below), whose sum is σ = 37425024. Its totient is φ = 10756800.

The previous prime is 20493383. The next prime is 20493409. The reversal of 20493405 is 50439402.

It is not a de Polignac number, because 20493405 - 2⁵ = 20493373 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20493409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 122632 + ... + 122798.

It is an arithmetic number, because the mean of its divisors is an integer number (779688).

Almost surely, 2^20493405 is an apocalyptic number.

It is an amenable number.

20493405 is a deficient number, since it is larger than the sum of its proper divisors (16931619).

20493405 is a wasteful number, since it uses less digits than its factorization.

20493405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288 (or 276 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20493405 is about 4526.9642145703. The cubic root of 20493405 is about 273.6558317501.

The spelling of 20493405 in words is "twenty million, four hundred ninety-three thousand, four hundred five".