1306921 has 12 divisors (see below), whose sum is σ = 1642816. Its totient is φ = 1017720.

The previous prime is 1306913. The next prime is 1306933. The reversal of 1306921 is 1296031.

It is not a de Polignac number, because 1306921 - 2³ = 1306913 is a prime.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

1306921 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1306892 and 1306901.

It is not an unprimeable number, because it can be changed into a prime (1306901) 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 11 ways as a sum of consecutive naturals, for example, 76 + ... + 1618.

2^1306921 is an apocalyptic number.

1306921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1306921 is a deficient number, since it is larger than the sum of its proper divisors (335895).

1306921 is a wasteful number, since it uses less digits than its factorization.

1306921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1572 (or 1561 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1306921 is about 1143.2064555451. The cubic root of 1306921 is about 109.3326258712.

The spelling of 1306921 in words is "one million, three hundred six thousand, nine hundred twenty-one".