89436721 has 4 divisors (see below), whose sum is σ = 97567344. Its totient is φ = 81306100.

The previous prime is 89436707. The next prime is 89436727. The reversal of 89436721 is 12763498.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 89436721 - 2¹¹ = 89434673 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (89436727) 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, 4065295 + ... + 4065316.

It is an arithmetic number, because the mean of its divisors is an integer number (24391836).

Almost surely, 2^89436721 is an apocalyptic number.

It is an amenable number.

89436721 is a deficient number, since it is larger than the sum of its proper divisors (8130623).

89436721 is a wasteful number, since it uses less digits than its factorization.

89436721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8130622.

The product of its digits is 72576, while the sum is 40.

The square root of 89436721 is about 9457.0989737868. The cubic root of 89436721 is about 447.2035984432.

The spelling of 89436721 in words is "eighty-nine million, four hundred thirty-six thousand, seven hundred twenty-one".