387213091 has 4 divisors (see below), whose sum is σ = 387737800. Its totient is φ = 386688384.

The previous prime is 387213077. The next prime is 387213109. The reversal of 387213091 is 190312783.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190312783 = 149 ⋅1277267.

It is a cyclic number.

It is not a de Polignac number, because 387213091 - 2²³ = 378824483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (387213791) 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, 261246 + ... + 262723.

It is an arithmetic number, because the mean of its divisors is an integer number (96934450).

Almost surely, 2^387213091 is an apocalyptic number.

387213091 is a deficient number, since it is larger than the sum of its proper divisors (524709).

387213091 is an equidigital number, since it uses as much as digits as its factorization.

387213091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 524708.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 387213091 is about 19677.7308397081. The cubic root of 387213091 is about 728.8698914713.

The spelling of 387213091 in words is "three hundred eighty-seven million, two hundred thirteen thousand, ninety-one".