687070091 has 2 divisors, whose sum is σ = 687070092. Its totient is φ = 687070090.

The previous prime is 687070073. The next prime is 687070123. The reversal of 687070091 is 190070786.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-687070091 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (687070061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343535045 + 343535046.

It is an arithmetic number, because the mean of its divisors is an integer number (343535046).

Almost surely, 2^687070091 is an apocalyptic number.

687070091 is a deficient number, since it is larger than the sum of its proper divisors (1).

687070091 is an equidigital number, since it uses as much as digits as its factorization.

687070091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 687070091 is about 26212.0218792828. The cubic root of 687070091 is about 882.4030783783.

The spelling of 687070091 in words is "six hundred eighty-seven million, seventy thousand, ninety-one".