1921537 has 2 divisors, whose sum is σ = 1921538. Its totient is φ = 1921536.

The previous prime is 1921531. The next prime is 1921553. The reversal of 1921537 is 7351291.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1073296 + 848241 = 1036^2 + 921^2 .

It is a cyclic number.

It is not a de Polignac number, because 1921537 - 2³ = 1921529 is a prime.

It is not a weakly prime, because it can be changed into another prime (1921531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 960768 + 960769.

It is an arithmetic number, because the mean of its divisors is an integer number (960769).

2^1921537 is an apocalyptic number.

It is an amenable number.

1921537 is a deficient number, since it is larger than the sum of its proper divisors (1).

1921537 is an equidigital number, since it uses as much as digits as its factorization.

1921537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1890, while the sum is 28.

The square root of 1921537 is about 1386.1951522062. The cubic root of 1921537 is about 124.3224567836.

The spelling of 1921537 in words is "one million, nine hundred twenty-one thousand, five hundred thirty-seven".