87640851791 has 32 divisors (see below), whose sum is σ = 100389155328. Its totient is φ = 76046248960.

The previous prime is 87640851743. The next prime is 87640851797. The reversal of 87640851791 is 19715804678.

It is a happy number.

It is not a de Polignac number, because 87640851791 - 2¹⁴ = 87640835407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87640851797) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1297640 + ... + 1363506.

It is an arithmetic number, because the mean of its divisors is an integer number (3137161104).

Almost surely, 2^87640851791 is an apocalyptic number.

87640851791 is a deficient number, since it is larger than the sum of its proper divisors (12748303537).

87640851791 is a wasteful number, since it uses less digits than its factorization.

87640851791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66031.

The product of its (nonzero) digits is 3386880, while the sum is 56.

The spelling of 87640851791 in words is "eighty-seven billion, six hundred forty million, eight hundred fifty-one thousand, seven hundred ninety-one".