1491021 has 40 divisors (see below), whose sum is σ = 2688960. Its totient is φ = 814968.

The previous prime is 1491013. The next prime is 1491031. The reversal of 1491021 is 1201941.

It is not a de Polignac number, because 1491021 - 2³ = 1491013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1490985 and 1491003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1491001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 64816 + ... + 64838.

It is an arithmetic number, because the mean of its divisors is an integer number (67224).

2^1491021 is an apocalyptic number.

It is an amenable number.

1491021 is a deficient number, since it is larger than the sum of its proper divisors (1197939).

1491021 is an frugal number, since it uses more digits than its factorization.

1491021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60 (or 33 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 1491021 is about 1221.0737078490. The cubic root of 1491021 is about 114.2425583337.

Adding to 1491021 its reverse (1201941), we get a palindrome (2692962).

The spelling of 1491021 in words is "one million, four hundred ninety-one thousand, twenty-one".