1806945381 has 16 divisors (see below), whose sum is σ = 2679072000. Its totient is φ = 1203678144.

The previous prime is 1806945341. The next prime is 1806945397. The reversal of 1806945381 is 1835496081.

1806945381 is a `hidden beast` number, since 180 + 6 + 94 + 5 + 381 = 666.

It is not a de Polignac number, because 1806945381 - 2¹³ = 1806937189 is a prime.

It is a super-2 number, since 2×1806945381² = 6530103219834470322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1806945341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9220 + ... + 60818.

It is an arithmetic number, because the mean of its divisors is an integer number (167442000).

Almost surely, 2^1806945381 is an apocalyptic number.

It is an amenable number.

1806945381 is a deficient number, since it is larger than the sum of its proper divisors (872126619).

1806945381 is a wasteful number, since it uses less digits than its factorization.

1806945381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52905 (or 52899 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 1806945381 is about 42508.1801657046. The cubic root of 1806945381 is about 1218.0029544445.

The spelling of 1806945381 in words is "one billion, eight hundred six million, nine hundred forty-five thousand, three hundred eighty-one".