27921390 has 64 divisors (see below), whose sum is σ = 79073280. Its totient is φ = 6174720.

The previous prime is 27921373. The next prime is 27921391. The reversal of 27921390 is 9312972.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27921391) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4366 + ... + 8654.

It is an arithmetic number, because the mean of its divisors is an integer number (1235520).

Almost surely, 2^27921390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27921390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39536640).

27921390 is an abundant number, since it is smaller than the sum of its proper divisors (51151890).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27921390 is a wasteful number, since it uses less digits than its factorization.

27921390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4337.

The product of its (nonzero) digits is 6804, while the sum is 33.

The square root of 27921390 is about 5284.0694545019. The cubic root of 27921390 is about 303.3744567144.

The spelling of 27921390 in words is "twenty-seven million, nine hundred twenty-one thousand, three hundred ninety".