19908993 has 24 divisors (see below), whose sum is σ = 29655808. Its totient is φ = 11809728.

The previous prime is 19908953. The next prime is 19909061. The reversal of 19908993 is 39980991.

It is not a de Polignac number, because 19908993 - 2⁶ = 19908929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19908943) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 32496 + ... + 33102.

Almost surely, 2^19908993 is an apocalyptic number.

19908993 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

19908993 is a deficient number, since it is larger than the sum of its proper divisors (9746815).

19908993 is a wasteful number, since it uses less digits than its factorization.

19908993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681 (or 652 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 48.

The square root of 19908993 is about 4461.9494618384. The cubic root of 19908993 is about 271.0294172484.

The spelling of 19908993 in words is "nineteen million, nine hundred eight thousand, nine hundred ninety-three".