187820857465 has 4 divisors (see below), whose sum is σ = 225385028964. Its totient is φ = 150256685968.

The previous prime is 187820857397. The next prime is 187820857487. The reversal of 187820857465 is 564758028781.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 139063359744 + 48757497721 = 372912^2 + 220811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187820857465 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18782085742 + ... + 18782085751.

It is an arithmetic number, because the mean of its divisors is an integer number (56346257241).

Almost surely, 2^187820857465 is an apocalyptic number.

It is an amenable number.

187820857465 is a deficient number, since it is larger than the sum of its proper divisors (37564171499).

187820857465 is an equidigital number, since it uses as much as digits as its factorization.

187820857465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37564171498.

The product of its (nonzero) digits is 30105600, while the sum is 61.

The spelling of 187820857465 in words is "one hundred eighty-seven billion, eight hundred twenty million, eight hundred fifty-seven thousand, four hundred sixty-five".