187274989 has 4 divisors (see below), whose sum is σ = 204300000. Its totient is φ = 170249980.

The previous prime is 187274897. The next prime is 187275007. The reversal of 187274989 is 989472781.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 187274989 - 2⁷ = 187274861 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187274189) 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, 8512489 + ... + 8512510.

It is an arithmetic number, because the mean of its divisors is an integer number (51075000).

Almost surely, 2^187274989 is an apocalyptic number.

It is an amenable number.

187274989 is a deficient number, since it is larger than the sum of its proper divisors (17025011).

187274989 is a wasteful number, since it uses less digits than its factorization.

187274989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17025010.

The product of its digits is 2032128, while the sum is 55.

The square root of 187274989 is about 13684.8452311307. The cubic root of 187274989 is about 572.1280755882.

It can be divided in two parts, 18727 and 4989, that added together give a square (23716 = 154²).

The spelling of 187274989 in words is "one hundred eighty-seven million, two hundred seventy-four thousand, nine hundred eighty-nine".