1813953620 has 24 divisors (see below), whose sum is σ = 3881178504. Its totient is φ = 711890816.

The previous prime is 1813953599. The next prime is 1813953649. The reversal of 1813953620 is 263593181.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 82228624 + 1731724996 = 9068^2 + 41614^2 .

It is a super-2 number, since 2×1813953620² = 6580855471022208800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 854579 + ... + 856698.

It is an arithmetic number, because the mean of its divisors is an integer number (161715771).

Almost surely, 2^1813953620 is an apocalyptic number.

1813953620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1813953620 is an abundant number, since it is smaller than the sum of its proper divisors (2067224884).

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

1813953620 is a wasteful number, since it uses less digits than its factorization.

1813953620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1711339 (or 1711337 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 1813953620 is about 42590.5343943933. The cubic root of 1813953620 is about 1219.5755981476.

The spelling of 1813953620 in words is "one billion, eight hundred thirteen million, nine hundred fifty-three thousand, six hundred twenty".