19990401 has 8 divisors (see below), whose sum is σ = 26814144. Its totient is φ = 13246800.

The previous prime is 19990391. The next prime is 19990403. The reversal of 19990401 is 10409991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-19990401 is a prime.

It is a super-2 number, since 2×19990401² = 799232264281602, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19990403) 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, 19450 + ... + 20451.

It is an arithmetic number, because the mean of its divisors is an integer number (3351768).

Almost surely, 2^19990401 is an apocalyptic number.

It is an amenable number.

19990401 is a deficient number, since it is larger than the sum of its proper divisors (6823743).

19990401 is a wasteful number, since it uses less digits than its factorization.

19990401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40071.

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 19990401 is about 4471.0626253722. The cubic root of 19990401 is about 271.3983285523.

The spelling of 19990401 in words is "nineteen million, nine hundred ninety thousand, four hundred one".