918382021 has 4 divisors (see below), whose sum is σ = 937922112. Its totient is φ = 898841932.

The previous prime is 918382013. The next prime is 918382027. The reversal of 918382021 is 120283819.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120283819 = 1361 ⋅88379.

It is a cyclic number.

It is not a de Polignac number, because 918382021 - 2³ = 918382013 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 (918382027) 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, 9769975 + ... + 9770068.

It is an arithmetic number, because the mean of its divisors is an integer number (234480528).

Almost surely, 2^918382021 is an apocalyptic number.

It is an amenable number.

918382021 is a deficient number, since it is larger than the sum of its proper divisors (19540091).

918382021 is a wasteful number, since it uses less digits than its factorization.

918382021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19540090.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 918382021 is about 30304.8184452572. The cubic root of 918382021 is about 972.0183364732.

It can be divided in two parts, 9183 and 82021, that added together give a square (91204 = 302²).

The spelling of 918382021 in words is "nine hundred eighteen million, three hundred eighty-two thousand, twenty-one".