20742447 has 16 divisors (see below), whose sum is σ = 30538368. Its totient is φ = 12418080.

The previous prime is 20742443. The next prime is 20742461. The reversal of 20742447 is 74424702.

It is not a de Polignac number, because 20742447 - 2² = 20742443 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20742443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1048 + ... + 6525.

It is an arithmetic number, because the mean of its divisors is an integer number (1908648).

Almost surely, 2^20742447 is an apocalyptic number.

20742447 is a deficient number, since it is larger than the sum of its proper divisors (9795921).

20742447 is a wasteful number, since it uses less digits than its factorization.

20742447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7670.

The product of its (nonzero) digits is 12544, while the sum is 30.

The square root of 20742447 is about 4554.3876646592. The cubic root of 20742447 is about 274.7598873795.

The spelling of 20742447 in words is "twenty million, seven hundred forty-two thousand, four hundred forty-seven".