19393988 has 12 divisors (see below), whose sum is σ = 34086780. Its totient is φ = 9654912.

The previous prime is 19393981. The next prime is 19394027. The reversal of 19393988 is 88939391.

It can be written as a sum of positive squares in 2 ways, for example, as 4401604 + 14992384 = 2098^2 + 3872^2 .

It is a super-2 number, since 2×19393988² = 752253541088288, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19393981) 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, 9473 + ... + 11336.

It is an arithmetic number, because the mean of its divisors is an integer number (2840565).

Almost surely, 2^19393988 is an apocalyptic number.

It is an amenable number.

19393988 is a deficient number, since it is larger than the sum of its proper divisors (14692792).

19393988 is a wasteful number, since it uses less digits than its factorization.

19393988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21046 (or 21044 counting only the distinct ones).

The product of its digits is 419904, while the sum is 50.

The square root of 19393988 is about 4403.8605790829. The cubic root of 19393988 is about 268.6719789383.

The spelling of 19393988 in words is "nineteen million, three hundred ninety-three thousand, nine hundred eighty-eight".