1918359421 has 4 divisors (see below), whose sum is σ = 2092755744. Its totient is φ = 1743963100.

The previous prime is 1918359383. The next prime is 1918359427. The reversal of 1918359421 is 1249538191.

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.

It is not a de Polignac number, because 1918359421 - 2¹¹ = 1918357373 is a prime.

It is a super-3 number, since 3×1918359421³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1918359427) 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, 87198145 + ... + 87198166.

It is an arithmetic number, because the mean of its divisors is an integer number (523188936).

Almost surely, 2^1918359421 is an apocalyptic number.

1918359421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1918359421 is a deficient number, since it is larger than the sum of its proper divisors (174396323).

1918359421 is a wasteful number, since it uses less digits than its factorization.

1918359421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174396322.

The product of its digits is 77760, while the sum is 43.

The square root of 1918359421 is about 43799.0801387426. The cubic root of 1918359421 is about 1242.5388973109.

The spelling of 1918359421 in words is "one billion, nine hundred eighteen million, three hundred fifty-nine thousand, four hundred twenty-one".