90729971 has 4 divisors (see below), whose sum is σ = 90963600. Its totient is φ = 90496344.

The previous prime is 90729953. The next prime is 90729979. The reversal of 90729971 is 17992709.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17992709 = 7 ⋅2570387.

It is a cyclic number.

It is not a de Polignac number, because 90729971 - 2⁶ = 90729907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90729979) 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, 116231 + ... + 117008.

It is an arithmetic number, because the mean of its divisors is an integer number (22740900).

Almost surely, 2^90729971 is an apocalyptic number.

90729971 is a deficient number, since it is larger than the sum of its proper divisors (233629).

90729971 is a wasteful number, since it uses less digits than its factorization.

90729971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233628.

The product of its (nonzero) digits is 71442, while the sum is 44.

The square root of 90729971 is about 9525.2281337509. The cubic root of 90729971 is about 449.3488046112.

The spelling of 90729971 in words is "ninety million, seven hundred twenty-nine thousand, nine hundred seventy-one".