20009457 has 32 divisors (see below), whose sum is σ = 32278400. Its totient is φ = 12177216.

The previous prime is 20009453. The next prime is 20009497. The reversal of 20009457 is 75490002.

20009457 is a `hidden beast` number, since 200 + 0 + 9 + 457 = 666.

It is not a de Polignac number, because 20009457 - 2² = 20009453 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20009457.

It is not an unprimeable number, because it can be changed into a prime (20009453) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37998 + ... + 38520.

It is an arithmetic number, because the mean of its divisors is an integer number (1008700).

Almost surely, 2^20009457 is an apocalyptic number.

20009457 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20009457 is a deficient number, since it is larger than the sum of its proper divisors (12268943).

20009457 is a wasteful number, since it uses less digits than its factorization.

20009457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654 (or 648 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 20009457 is about 4473.1931547833. The cubic root of 20009457 is about 271.4845386635.

Adding to 20009457 its reverse (75490002), we get a palindrome (95499459).

The spelling of 20009457 in words is "twenty million, nine thousand, four hundred fifty-seven".