19401139 has 4 divisors (see below), whose sum is σ = 19410160. Its totient is φ = 19392120.

The previous prime is 19401091. The next prime is 19401143. The reversal of 19401139 is 93110491.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 19401139 - 2⁹ = 19400627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19401149) 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, 802 + ... + 6280.

It is an arithmetic number, because the mean of its divisors is an integer number (4852540).

Almost surely, 2^19401139 is an apocalyptic number.

19401139 is a deficient number, since it is larger than the sum of its proper divisors (9021).

19401139 is an equidigital number, since it uses as much as digits as its factorization.

19401139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9020.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 19401139 is about 4404.6724055258. The cubic root of 19401139 is about 268.7049966829.

The spelling of 19401139 in words is "nineteen million, four hundred one thousand, one hundred thirty-nine".