19688157 has 8 divisors (see below), whose sum is σ = 29167680. Its totient is φ = 13125420.

The previous prime is 19688153. The next prime is 19688167. The reversal of 19688157 is 75188691.

It is not a de Polignac number, because 19688157 - 2² = 19688153 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19688153) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364569 + ... + 364622.

It is an arithmetic number, because the mean of its divisors is an integer number (3645960).

Almost surely, 2^19688157 is an apocalyptic number.

It is an amenable number.

19688157 is a deficient number, since it is larger than the sum of its proper divisors (9479523).

19688157 is an equidigital number, since it uses as much as digits as its factorization.

19688157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729200 (or 729194 counting only the distinct ones).

The product of its digits is 120960, while the sum is 45.

The square root of 19688157 is about 4437.1338722198. The cubic root of 19688157 is about 270.0235781879.

The spelling of 19688157 in words is "nineteen million, six hundred eighty-eight thousand, one hundred fifty-seven".