1820628540 has 72 divisors (see below), whose sum is σ = 5574245040. Its totient is φ = 480958464.

The previous prime is 1820628517. The next prime is 1820628571. The reversal of 1820628540 is 458260281.

1820628540 is a `hidden beast` number, since 1 + 8 + 20 + 628 + 5 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1820628495 and 1820628504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28005 + ... + 66524.

It is an arithmetic number, because the mean of its divisors is an integer number (77420070).

Almost surely, 2^1820628540 is an apocalyptic number.

1820628540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1820628540 is an abundant number, since it is smaller than the sum of its proper divisors (3753616500).

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

1820628540 is a wasteful number, since it uses less digits than its factorization.

1820628540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94651 (or 94646 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 1820628540 is about 42668.8239819192. The cubic root of 1820628540 is about 1221.0696835350.

The spelling of 1820628540 in words is "one billion, eight hundred twenty million, six hundred twenty-eight thousand, five hundred forty".