87978409 has 8 divisors (see below), whose sum is σ = 89637120. Its totient is φ = 86326800.

The previous prime is 87978367. The next prime is 87978419. The reversal of 87978409 is 90487978.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 87978409 - 2¹⁹ = 87454121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87978419) 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, 27714 + ... + 30724.

It is an arithmetic number, because the mean of its divisors is an integer number (11204640).

Almost surely, 2^87978409 is an apocalyptic number.

It is an amenable number.

87978409 is a deficient number, since it is larger than the sum of its proper divisors (1658711).

87978409 is a wasteful number, since it uses less digits than its factorization.

87978409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3551.

The product of its (nonzero) digits is 1016064, while the sum is 52.

The square root of 87978409 is about 9379.6806448834. The cubic root of 87978409 is about 444.7596379004.

The spelling of 87978409 in words is "eighty-seven million, nine hundred seventy-eight thousand, four hundred nine".