20428471 has 8 divisors (see below), whose sum is σ = 23469344. Its totient is φ = 17418240.

The previous prime is 20428469. The next prime is 20428487. The reversal of 20428471 is 17482402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20428471 - 2¹ = 20428469 is a prime.

It is a super-3 number, since 3×20428471³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6210 + ... + 8911.

It is an arithmetic number, because the mean of its divisors is an integer number (2933668).

Almost surely, 2^20428471 is an apocalyptic number.

20428471 is the 2610-th hex number.

20428471 is a deficient number, since it is larger than the sum of its proper divisors (3040873).

20428471 is a wasteful number, since it uses less digits than its factorization.

20428471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15321.

The product of its (nonzero) digits is 3584, while the sum is 28.

The square root of 20428471 is about 4519.7866100072. The cubic root of 20428471 is about 273.3664969015.

The spelling of 20428471 in words is "twenty million, four hundred twenty-eight thousand, four hundred seventy-one".