91970213 has 4 divisors (see below), whose sum is σ = 92030988. Its totient is φ = 91909440.

The previous prime is 91970183. The next prime is 91970227. The reversal of 91970213 is 31207919.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 18130564 + 73839649 = 4258^2 + 8593^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91970213 is a prime.

It is a super-3 number, since 3×91970213³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91970213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91970413) 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, 28058 + ... + 31163.

It is an arithmetic number, because the mean of its divisors is an integer number (23007747).

Almost surely, 2^91970213 is an apocalyptic number.

It is an amenable number.

91970213 is a deficient number, since it is larger than the sum of its proper divisors (60775).

91970213 is a wasteful number, since it uses less digits than its factorization.

91970213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60774.

The product of its (nonzero) digits is 3402, while the sum is 32.

The square root of 91970213 is about 9590.1101662077. The cubic root of 91970213 is about 451.3870175764.

The spelling of 91970213 in words is "ninety-one million, nine hundred seventy thousand, two hundred thirteen".