87771823 has 2 divisors, whose sum is σ = 87771824. Its totient is φ = 87771822.

The previous prime is 87771821. The next prime is 87771839. The reversal of 87771823 is 32817778.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 87771823 - 2¹ = 87771821 is a prime.

Together with 87771821, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 87771823.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87771821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43885911 + 43885912.

It is an arithmetic number, because the mean of its divisors is an integer number (43885912).

Almost surely, 2^87771823 is an apocalyptic number.

87771823 is a deficient number, since it is larger than the sum of its proper divisors (1).

87771823 is an equidigital number, since it uses as much as digits as its factorization.

87771823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131712, while the sum is 43.

The square root of 87771823 is about 9368.6617507518. The cubic root of 87771823 is about 444.4112451289.

The spelling of 87771823 in words is "eighty-seven million, seven hundred seventy-one thousand, eight hundred twenty-three".