99210857 has 4 divisors (see below), whose sum is σ = 101630676. Its totient is φ = 96791040.

The previous prime is 99210851. The next prime is 99210877. The reversal of 99210857 is 75801299.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75801299 = 7 ⋅10828757.

It can be written as a sum of positive squares in 2 ways, for example, as 18498601 + 80712256 = 4301^2 + 8984^2 .

It is a cyclic number.

It is not a de Polignac number, because 99210857 - 2¹² = 99206761 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41), and also a Moran number because the ratio is a prime number: 2419777 = 99210857 / (9 + 9 + 2 + 1 + 0 + 8 + 5 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99210851) 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, 1209848 + ... + 1209929.

It is an arithmetic number, because the mean of its divisors is an integer number (25407669).

Almost surely, 2^99210857 is an apocalyptic number.

It is an amenable number.

99210857 is a deficient number, since it is larger than the sum of its proper divisors (2419819).

99210857 is a wasteful number, since it uses less digits than its factorization.

99210857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2419818.

The product of its (nonzero) digits is 45360, while the sum is 41.

The square root of 99210857 is about 9960.4646979948. The cubic root of 99210857 is about 462.9346983895.

The spelling of 99210857 in words is "ninety-nine million, two hundred ten thousand, eight hundred fifty-seven".