1722990 has 32 divisors (see below), whose sum is σ = 4193280. Its totient is φ = 453024.

The previous prime is 1722989. The next prime is 1722991. The reversal of 1722990 is 992271.

It is an interprime number because it is at equal distance from previous prime (1722989) and next prime (1722991).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1722991) 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 15 ways as a sum of consecutive naturals, for example, 2007 + ... + 2733.

It is an arithmetic number, because the mean of its divisors is an integer number (131040).

2^1722990 is an apocalyptic number.

1722990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1722990 is an abundant number, since it is smaller than the sum of its proper divisors (2470290).

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

1722990 is a wasteful number, since it uses less digits than its factorization.

1722990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 816.

The product of its (nonzero) digits is 2268, while the sum is 30.

The square root of 1722990 is about 1312.6271366995. The cubic root of 1722990 is about 119.8839155173.

The spelling of 1722990 in words is "one million, seven hundred twenty-two thousand, nine hundred ninety".