19581237142 has 4 divisors (see below), whose sum is σ = 29371855716. Its totient is φ = 9790618570.

The previous prime is 19581237127. The next prime is 19581237209. The reversal of 19581237142 is 24173218591.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×19581237142² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4895309284 + ... + 4895309287.

It is an arithmetic number, because the mean of its divisors is an integer number (7342963929).

Almost surely, 2^19581237142 is an apocalyptic number.

19581237142 is a deficient number, since it is larger than the sum of its proper divisors (9790618574).

19581237142 is an equidigital number, since it uses as much as digits as its factorization.

19581237142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9790618573.

The product of its digits is 120960, while the sum is 43.

The spelling of 19581237142 in words is "nineteen billion, five hundred eighty-one million, two hundred thirty-seven thousand, one hundred forty-two".