108391421 has 4 divisors (see below), whose sum is σ = 108427452. Its totient is φ = 108355392.

The previous prime is 108391411. The next prime is 108391427. The reversal of 108391421 is 124193801.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99900025 + 8491396 = 9995^2 + 2914^2 .

It is a cyclic number.

It is not a de Polignac number, because 108391421 - 2¹⁰ = 108390397 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 (108391427) 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, 13046 + ... + 19671.

It is an arithmetic number, because the mean of its divisors is an integer number (27106863).

Almost surely, 2^108391421 is an apocalyptic number.

It is an amenable number.

108391421 is a deficient number, since it is larger than the sum of its proper divisors (36031).

108391421 is an equidigital number, since it uses as much as digits as its factorization.

108391421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36030.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 108391421 is about 10411.1200646232. The cubic root of 108391421 is about 476.7949387183.

The spelling of 108391421 in words is "one hundred eight million, three hundred ninety-one thousand, four hundred twenty-one".