189938795987 has 4 divisors (see below), whose sum is σ = 189970233240. Its totient is φ = 189907358736.

The previous prime is 189938795957. The next prime is 189938796037. The reversal of 189938795987 is 789597839981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789597839981 = 2221 ⋅355514561.

It is a cyclic number.

It is not a de Polignac number, because 189938795987 - 2¹² = 189938791891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189938795957) 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, 15709562 + ... + 15721647.

It is an arithmetic number, because the mean of its divisors is an integer number (47492558310).

Almost surely, 2^189938795987 is an apocalyptic number.

189938795987 is a deficient number, since it is larger than the sum of its proper divisors (31437253).

189938795987 is an equidigital number, since it uses as much as digits as its factorization.

189938795987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31437252.

The product of its digits is 2469035520, while the sum is 83.

The spelling of 189938795987 in words is "one hundred eighty-nine billion, nine hundred thirty-eight million, seven hundred ninety-five thousand, nine hundred eighty-seven".