7858491987 has 8 divisors (see below), whose sum is σ = 10478407104. Its totient is φ = 5238785768.

The previous prime is 7858491947. The next prime is 7858492003. The reversal of 7858491987 is 7891948587.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7858491987 - 2⁸ = 7858491731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7858491917) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 94228 + ... + 156830.

It is an arithmetic number, because the mean of its divisors is an integer number (1309800888).

Almost surely, 2^7858491987 is an apocalyptic number.

7858491987 is a deficient number, since it is larger than the sum of its proper divisors (2619915117).

7858491987 is a wasteful number, since it uses less digits than its factorization.

7858491987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104449.

The product of its digits is 40642560, while the sum is 66.

The square root of 7858491987 is about 88648.1358348837. The cubic root of 7858491987 is about 1988.1374445813.

The spelling of 7858491987 in words is "seven billion, eight hundred fifty-eight million, four hundred ninety-one thousand, nine hundred eighty-seven".