1156820 has 24 divisors (see below), whose sum is σ = 2776704. Its totient is φ = 396576.

The previous prime is 1156819. The next prime is 1156823. The reversal of 1156820 is 286511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1156823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3992 + ... + 4271.

It is an arithmetic number, because the mean of its divisors is an integer number (115696).

2^1156820 is an apocalyptic number.

1156820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1156820 is an abundant number, since it is smaller than the sum of its proper divisors (1619884).

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

1156820 is a wasteful number, since it uses less digits than its factorization.

1156820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8279 (or 8277 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 1156820 is about 1075.5556703398. Note that the first 3 decimals coincide. The cubic root of 1156820 is about 104.9756557319.

The spelling of 1156820 in words is "one million, one hundred fifty-six thousand, eight hundred twenty".