1921497 has 4 divisors (see below), whose sum is σ = 2562000. Its totient is φ = 1280996.

The previous prime is 1921483. The next prime is 1921499. The reversal of 1921497 is 7941291.

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, and also an emirpimes, since its reverse is a distinct semiprime: 7941291 = 3 ⋅2647097.

It is a cyclic number.

It is not a de Polignac number, because 1921497 - 2⁴ = 1921481 is a prime.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (1921499) 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, 320247 + ... + 320252.

It is an arithmetic number, because the mean of its divisors is an integer number (640500).

2^1921497 is an apocalyptic number.

It is an amenable number.

1921497 is a deficient number, since it is larger than the sum of its proper divisors (640503).

1921497 is an equidigital number, since it uses as much as digits as its factorization.

1921497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 640502.

The product of its digits is 4536, while the sum is 33.

The square root of 1921497 is about 1386.1807241482. The cubic root of 1921497 is about 124.3215941178.

The spelling of 1921497 in words is "one million, nine hundred twenty-one thousand, four hundred ninety-seven".