213000991 has 18 divisors (see below), whose sum is σ = 251195352. Its totient is φ = 180086760.

The previous prime is 213000989. The next prime is 213001003. The reversal of 213000991 is 199000312.

213000991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 213000991 - 2¹ = 213000989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213000961) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 337246 + ... + 337876.

Almost surely, 2^213000991 is an apocalyptic number.

213000991 is a deficient number, since it is larger than the sum of its proper divisors (38194361).

213000991 is an frugal number, since it uses more digits than its factorization.

213000991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811 (or 721 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 25.

The square root of 213000991 is about 14594.5534703875. The cubic root of 213000991 is about 597.2101881696.

The spelling of 213000991 in words is "two hundred thirteen million, nine hundred ninety-one", and thus it is an aban number.