120821355 has 16 divisors (see below), whose sum is σ = 214793760. Its totient is φ = 64437984.

The previous prime is 120821341. The next prime is 120821359. The reversal of 120821355 is 553128021.

It is a happy number.

It is not a de Polignac number, because 120821355 - 2¹⁰ = 120820331 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (120821359) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 447352 + ... + 447621.

It is an arithmetic number, because the mean of its divisors is an integer number (13424610).

Almost surely, 2^120821355 is an apocalyptic number.

120821355 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

120821355 is a deficient number, since it is larger than the sum of its proper divisors (93972405).

120821355 is an equidigital number, since it uses as much as digits as its factorization.

120821355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894987 (or 894981 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 120821355 is about 10991.8767733267. The cubic root of 120821355 is about 494.3652101663.

Adding to 120821355 its reverse (553128021), we get a palindrome (673949376).

The spelling of 120821355 in words is "one hundred twenty million, eight hundred twenty-one thousand, three hundred fifty-five".