355981 has 4 divisors (see below), whose sum is σ = 358912. Its totient is φ = 353052.

The previous prime is 355969. The next prime is 356023. The reversal of 355981 is 189553.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 355981 - 2⁷ = 355853 is a prime.

It is a super-2 number, since 2×355981² = 253444944722, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (355951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1275 + ... + 1528.

It is an arithmetic number, because the mean of its divisors is an integer number (89728).

2³⁵⁵⁹⁸¹ is an apocalyptic number.

It is an amenable number.

355981 is a deficient number, since it is larger than the sum of its proper divisors (2931).

355981 is a wasteful number, since it uses less digits than its factorization.

355981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2930.

The product of its digits is 5400, while the sum is 31.

The square root of 355981 is about 596.6414333584. The cubic root of 355981 is about 70.8721497360.

The spelling of 355981 in words is "three hundred fifty-five thousand, nine hundred eighty-one".