185307409820 has 48 divisors (see below), whose sum is σ = 422924668320. Its totient is φ = 67793469696.

The previous prime is 185307409817. The next prime is 185307409871. The reversal of 185307409820 is 28904703581.

It is a happy number.

It is a super-2 number, since 2×185307409820² (a number of 23 digits) 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 15 ways as a sum of consecutive naturals, for example, 3241022 + ... + 3297701.

It is an arithmetic number, because the mean of its divisors is an integer number (8810930590).

Almost surely, 2^185307409820 is an apocalyptic number.

185307409820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

185307409820 is an abundant number, since it is smaller than the sum of its proper divisors (237617258500).

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

185307409820 is a wasteful number, since it uses less digits than its factorization.

185307409820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6538854 (or 6538852 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 47.

The spelling of 185307409820 in words is "one hundred eighty-five billion, three hundred seven million, four hundred nine thousand, eight hundred twenty".