19748857 has 4 divisors (see below), whose sum is σ = 19763200. Its totient is φ = 19734516.

The previous prime is 19748831. The next prime is 19748867. The reversal of 19748857 is 75884791.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 75884791 = 7529 ⋅10079.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19748857 is a prime.

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 19748857.

It is not an unprimeable number, because it can be changed into a prime (19748867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4857 + ... + 7942.

It is an arithmetic number, because the mean of its divisors is an integer number (4940800).

Almost surely, 2^19748857 is an apocalyptic number.

It is an amenable number.

19748857 is a deficient number, since it is larger than the sum of its proper divisors (14343).

19748857 is a wasteful number, since it uses less digits than its factorization.

19748857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14342.

The product of its digits is 564480, while the sum is 49.

The square root of 19748857 is about 4443.9686092501. The cubic root of 19748857 is about 270.3007941761.

The spelling of 19748857 in words is "nineteen million, seven hundred forty-eight thousand, eight hundred fifty-seven".