20344857 has 32 divisors (see below), whose sum is σ = 31358208. Its totient is φ = 11632896.

The previous prime is 20344853. The next prime is 20344871. The reversal of 20344857 is 75844302.

It is not a de Polignac number, because 20344857 - 2² = 20344853 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20344853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32883 + ... + 33495.

It is an arithmetic number, because the mean of its divisors is an integer number (979944).

Almost surely, 2^20344857 is an apocalyptic number.

It is an amenable number.

20344857 is a deficient number, since it is larger than the sum of its proper divisors (11013351).

20344857 is a wasteful number, since it uses less digits than its factorization.

20344857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689.

The product of its (nonzero) digits is 26880, while the sum is 33.

The square root of 20344857 is about 4510.5273527604. The cubic root of 20344857 is about 272.9930226718.

The spelling of 20344857 in words is "twenty million, three hundred forty-four thousand, eight hundred fifty-seven".