190397987281 has 4 divisors (see below), whose sum is σ = 200418934000. Its totient is φ = 180377040564.

The previous prime is 190397987279. The next prime is 190397987323. The reversal of 190397987281 is 182789793091.

190397987281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 182789793091 = 1453 ⋅125801647.

It is a cyclic number.

It is not a de Polignac number, because 190397987281 - 2¹ = 190397987279 is a prime.

It is a super-2 number, since 2×190397987281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (190397987261) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 5010473331 + ... + 5010473368.

It is an arithmetic number, because the mean of its divisors is an integer number (50104733500).

Almost surely, 2^190397987281 is an apocalyptic number.

It is an amenable number.

190397987281 is a deficient number, since it is larger than the sum of its proper divisors (10020946719).

190397987281 is a wasteful number, since it uses less digits than its factorization.

190397987281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10020946718.

The product of its (nonzero) digits is 13716864, while the sum is 64.

The spelling of 190397987281 in words is "one hundred ninety billion, three hundred ninety-seven million, nine hundred eighty-seven thousand, two hundred eighty-one".