1205770820 has 24 divisors (see below), whose sum is σ = 2532779928. Its totient is φ = 482182400.

The previous prime is 1205770817. The next prime is 1205770831. The reversal of 1205770820 is 280775021.

It can be written as a sum of positive squares in 4 ways, for example, as 11930116 + 1193840704 = 3454^2 + 34552^2 .

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, 127040 + ... + 136200.

It is an arithmetic number, because the mean of its divisors is an integer number (105532497).

Almost surely, 2^1205770820 is an apocalyptic number.

1205770820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1205770820 is an abundant number, since it is smaller than the sum of its proper divisors (1327009108).

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

1205770820 is a wasteful number, since it uses less digits than its factorization.

1205770820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15751 (or 15749 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 1205770820 is about 34724.2108621636. The cubic root of 1205770820 is about 1064.3592934088.

The spelling of 1205770820 in words is "one billion, two hundred five million, seven hundred seventy thousand, eight hundred twenty".