1634921 has 4 divisors (see below), whose sum is σ = 1638144. Its totient is φ = 1631700.

The previous prime is 1634911. The next prime is 1634923. The reversal of 1634921 is 1294361.

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 1634921 - 2¹⁴ = 1618537 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1634923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 665 + ... + 1926.

It is an arithmetic number, because the mean of its divisors is an integer number (409536).

2^1634921 is an apocalyptic number.

It is an amenable number.

1634921 is a deficient number, since it is larger than the sum of its proper divisors (3223).

1634921 is an equidigital number, since it uses as much as digits as its factorization.

1634921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3222.

The product of its digits is 1296, while the sum is 26.

The square root of 1634921 is about 1278.6402934367. The cubic root of 1634921 is about 117.8055064718.

The spelling of 1634921 in words is "one million, six hundred thirty-four thousand, nine hundred twenty-one".