99640213 has 4 divisors (see below), whose sum is σ = 105501420. Its totient is φ = 93779008.

The previous prime is 99640187. The next prime is 99640241. The reversal of 99640213 is 31204699.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31204699 = 2531 ⋅12329.

It can be written as a sum of positive squares in 2 ways, for example, as 45131524 + 54508689 = 6718^2 + 7383^2 .

It is a cyclic number.

It is not a de Polignac number, because 99640213 - 2⁵ = 99640181 is a prime.

It is a super-3 number, since 3×99640213³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99640273) 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, 2930578 + ... + 2930611.

It is an arithmetic number, because the mean of its divisors is an integer number (26375355).

Almost surely, 2^99640213 is an apocalyptic number.

It is an amenable number.

99640213 is a deficient number, since it is larger than the sum of its proper divisors (5861207).

99640213 is a wasteful number, since it uses less digits than its factorization.

99640213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5861206.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 99640213 is about 9981.9944399904. The cubic root of 99640213 is about 463.6015533183.

It can be divided in two parts, 996 and 40213, that added together give a square (41209 = 203²).

The spelling of 99640213 in words is "ninety-nine million, six hundred forty thousand, two hundred thirteen".