19999457 has 8 divisors (see below), whose sum is σ = 21290400. Its totient is φ = 18732384.

The previous prime is 19999439. The next prime is 19999471. The reversal of 19999457 is 75499991.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19999457 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19999399 and 19999408.

It is not an unprimeable number, because it can be changed into a prime (19990457) 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 7 ways as a sum of consecutive naturals, for example, 4223 + ... + 7604.

It is an arithmetic number, because the mean of its divisors is an integer number (2661300).

Almost surely, 2^19999457 is an apocalyptic number.

It is an amenable number.

19999457 is a deficient number, since it is larger than the sum of its proper divisors (1290943).

19999457 is a wasteful number, since it uses less digits than its factorization.

19999457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11935.

The product of its digits is 918540, while the sum is 53.

The square root of 19999457 is about 4472.0752453419. The cubic root of 19999457 is about 271.4393050893.

The spelling of 19999457 in words is "nineteen million, nine hundred ninety-nine thousand, four hundred fifty-seven".