87921297 has 24 divisors (see below), whose sum is σ = 135196776. Its totient is φ = 54867456.

The previous prime is 87921289. The next prime is 87921299. The reversal of 87921297 is 79212978.

It can be written as a sum of positive squares in 4 ways, for example, as 78428736 + 9492561 = 8856^2 + 3081^2 .

It is not a de Polignac number, because 87921297 - 2³ = 87921289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (87921299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28683 + ... + 31599.

It is an arithmetic number, because the mean of its divisors is an integer number (5633199).

Almost surely, 2^87921297 is an apocalyptic number.

It is an amenable number.

87921297 is a deficient number, since it is larger than the sum of its proper divisors (47275479).

87921297 is a wasteful number, since it uses less digits than its factorization.

87921297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3137 (or 3134 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The square root of 87921297 is about 9376.6356973064. The cubic root of 87921297 is about 444.6633771202.

The spelling of 87921297 in words is "eighty-seven million, nine hundred twenty-one thousand, two hundred ninety-seven".