1220381 has 4 divisors (see below), whose sum is σ = 1228032. Its totient is φ = 1212732.

The previous prime is 1220369. The next prime is 1220393. The reversal of 1220381 is 1830221.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1830221 = 101 ⋅18121.

It is an interprime number because it is at equal distance from previous prime (1220369) and next prime (1220393).

It is a cyclic number.

It is not a de Polignac number, because 1220381 - 2¹⁰ = 1219357 is a prime.

It is a super-2 number, since 2×1220381² = 2978659570322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3581 + ... + 3906.

It is an arithmetic number, because the mean of its divisors is an integer number (307008).

2^1220381 is an apocalyptic number.

It is an amenable number.

1220381 is a deficient number, since it is larger than the sum of its proper divisors (7651).

1220381 is an equidigital number, since it uses as much as digits as its factorization.

1220381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7650.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1220381 is about 1104.7085588516. The cubic root of 1220381 is about 106.8640950765.

The spelling of 1220381 in words is "one million, two hundred twenty thousand, three hundred eighty-one".