99870961 has 4 divisors (see below), whose sum is σ = 100167652. Its totient is φ = 99574272.

The previous prime is 99870959. The next prime is 99870977. The reversal of 99870961 is 16907899.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16907899 = 29 ⋅583031.

It can be written as a sum of positive squares in 2 ways, for example, as 33350625 + 66520336 = 5775^2 + 8156^2 .

It is a 4-Lehmer number, since φ(99870961) divides (99870961-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 99870961 - 2¹ = 99870959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99870361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147840 + ... + 148513.

It is an arithmetic number, because the mean of its divisors is an integer number (25041913).

Almost surely, 2^99870961 is an apocalyptic number.

It is an amenable number.

99870961 is a deficient number, since it is larger than the sum of its proper divisors (296691).

99870961 is a wasteful number, since it uses less digits than its factorization.

99870961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296690.

The product of its (nonzero) digits is 244944, while the sum is 49.

The square root of 99870961 is about 9993.5459672731. The cubic root of 99870961 is about 463.9591487643.

The spelling of 99870961 in words is "ninety-nine million, eight hundred seventy thousand, nine hundred sixty-one".