1997021 has 8 divisors (see below), whose sum is σ = 2244480. Its totient is φ = 1762992.

The previous prime is 1997003. The next prime is 1997029. The reversal of 1997021 is 1207991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1997021 - 2¹⁴ = 1980637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1997029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3041 + ... + 3638.

It is an arithmetic number, because the mean of its divisors is an integer number (280560).

2^1997021 is an apocalyptic number.

It is an amenable number.

1997021 is a deficient number, since it is larger than the sum of its proper divisors (247459).

1997021 is a wasteful number, since it uses less digits than its factorization.

1997021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6715.

The product of its (nonzero) digits is 1134, while the sum is 29.

The square root of 1997021 is about 1413.1599343316. The cubic root of 1997021 is about 125.9295188250.

It can be divided in two parts, 19970 and 21, that added together give a palindrome (19991).

The spelling of 1997021 in words is "one million, nine hundred ninety-seven thousand, twenty-one".