69989987 has 4 divisors (see below), whose sum is σ = 70156656. Its totient is φ = 69823320.

The previous prime is 69989923. The next prime is 69990029. The reversal of 69989987 is 78998996.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 69989987 - 2⁶ = 69989923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (69980987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82703 + ... + 83544.

It is an arithmetic number, because the mean of its divisors is an integer number (17539164).

Almost surely, 2^69989987 is an apocalyptic number.

69989987 is a deficient number, since it is larger than the sum of its proper divisors (166669).

69989987 is a wasteful number, since it uses less digits than its factorization.

69989987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166668.

The product of its digits is 17635968, while the sum is 65.

The square root of 69989987 is about 8366.0018527371. The cubic root of 69989987 is about 412.1088783630.

Subtracting 69989987 from its reverse (78998996), we obtain a palindrome (9009009).

The spelling of 69989987 in words is "sixty-nine million, nine hundred eighty-nine thousand, nine hundred eighty-seven".