1520997 has 4 divisors (see below), whose sum is σ = 2028000. Its totient is φ = 1013996.

The previous prime is 1520989. The next prime is 1521011. The reversal of 1520997 is 7990251.

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.

It is a cyclic number.

It is not a de Polignac number, because 1520997 - 2³ = 1520989 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1520947) 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, 253497 + ... + 253502.

It is an arithmetic number, because the mean of its divisors is an integer number (507000).

2^1520997 is an apocalyptic number.

It is an amenable number.

1520997 is a deficient number, since it is larger than the sum of its proper divisors (507003).

1520997 is an equidigital number, since it uses as much as digits as its factorization.

1520997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507002.

The product of its (nonzero) digits is 5670, while the sum is 33.

The square root of 1520997 is about 1233.2870712044. The cubic root of 1520997 is about 115.0030749020.

It can be divided in two parts, 15 and 20997, that added together give a palindrome (21012).

The spelling of 1520997 in words is "one million, five hundred twenty thousand, nine hundred ninety-seven".