87189797 has 8 divisors (see below), whose sum is σ = 89671032. Its totient is φ = 84715200.

The previous prime is 87189779. The next prime is 87189811. The reversal of 87189797 is 79798178.

It can be written as a sum of positive squares in 4 ways, for example, as 44169316 + 43020481 = 6646^2 + 6559^2 .

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

It is not a de Polignac number, because 87189797 - 2⁸ = 87189541 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 (87189737) 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, 38147 + ... + 40367.

It is an arithmetic number, because the mean of its divisors is an integer number (11208879).

Almost surely, 2^87189797 is an apocalyptic number.

It is an amenable number.

87189797 is a deficient number, since it is larger than the sum of its proper divisors (2481235).

87189797 is a wasteful number, since it uses less digits than its factorization.

87189797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319.

The product of its digits is 1778112, while the sum is 56.

The square root of 87189797 is about 9337.5476973347. The cubic root of 87189797 is about 443.4267501838.

The spelling of 87189797 in words is "eighty-seven million, one hundred eighty-nine thousand, seven hundred ninety-seven".