187970945 has 4 divisors (see below), whose sum is σ = 225565140. Its totient is φ = 150376752.

The previous prime is 187970911. The next prime is 187970947. The reversal of 187970945 is 549079781.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 549079781 = 31 ⋅17712251.

It can be written as a sum of positive squares in 2 ways, for example, as 49014001 + 138956944 = 7001^2 + 11788^2 .

It is a cyclic number.

It is not a de Polignac number, because 187970945 - 2¹⁰ = 187969921 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 187970893 and 187970902.

It is not an unprimeable number, because it can be changed into a prime (187970947) 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, 18797090 + ... + 18797099.

It is an arithmetic number, because the mean of its divisors is an integer number (56391285).

Almost surely, 2^187970945 is an apocalyptic number.

It is an amenable number.

187970945 is a deficient number, since it is larger than the sum of its proper divisors (37594195).

187970945 is an equidigital number, since it uses as much as digits as its factorization.

187970945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37594194.

The product of its (nonzero) digits is 635040, while the sum is 50.

The square root of 187970945 is about 13710.2496330300. The cubic root of 187970945 is about 572.8359183666.

The spelling of 187970945 in words is "one hundred eighty-seven million, nine hundred seventy thousand, nine hundred forty-five".