1991022 has 32 divisors (see below), whose sum is σ = 4402944. Its totient is φ = 595200.

The previous prime is 1990987. The next prime is 1991027. The reversal of 1991022 is 2201991.

It is a junction number, because it is equal to n+sod(n) for n = 1990983 and 1991001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991027) 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, 6247 + ... + 6557.

It is an arithmetic number, because the mean of its divisors is an integer number (137592).

2^1991022 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1991022, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2201472).

1991022 is an abundant number, since it is smaller than the sum of its proper divisors (2411922).

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

1991022 is a wasteful number, since it uses less digits than its factorization.

1991022 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 424.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 1991022 is about 1411.0357897658. The cubic root of 1991022 is about 125.8032959994.

It can be divided in two parts, 199 and 1022, that added together give a palindrome (1221).

The spelling of 1991022 in words is "one million, nine hundred ninety-one thousand, twenty-two".