19971801 has 12 divisors (see below), whose sum is σ = 28910128. Its totient is φ = 13285944.

The previous prime is 19971761. The next prime is 19971857. The reversal of 19971801 is 10817991.

It is not a de Polignac number, because 19971801 - 2¹⁰ = 19970777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19971101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2586 + ... + 6828.

Almost surely, 2^19971801 is an apocalyptic number.

It is an amenable number.

19971801 is a deficient number, since it is larger than the sum of its proper divisors (8938327).

19971801 is a wasteful number, since it uses less digits than its factorization.

19971801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4772 (or 4769 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 36.

The square root of 19971801 is about 4468.9820988677. The cubic root of 19971801 is about 271.3141285513.

The spelling of 19971801 in words is "nineteen million, nine hundred seventy-one thousand, eight hundred one".