1811420938 has 4 divisors (see below), whose sum is σ = 2717131410. Its totient is φ = 905710468.

The previous prime is 1811420929. The next prime is 1811420981. The reversal of 1811420938 is 8390241181.

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

It can be written as a sum of positive squares in only one way, i.e., 907997689 + 903423249 = 30133^2 + 30057^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1811420897 and 1811420906.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 452855233 + ... + 452855236.

Almost surely, 2^1811420938 is an apocalyptic number.

1811420938 is a deficient number, since it is larger than the sum of its proper divisors (905710472).

1811420938 is an equidigital number, since it uses as much as digits as its factorization.

1811420938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905710471.

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 1811420938 is about 42560.7910875726. The cubic root of 1811420938 is about 1219.0077343396.

The spelling of 1811420938 in words is "one billion, eight hundred eleven million, four hundred twenty thousand, nine hundred thirty-eight".