1921761 has 12 divisors (see below), whose sum is σ = 2818192. Its totient is φ = 1261656.

The previous prime is 1921747. The next prime is 1921763. The reversal of 1921761 is 1671291.

It is not a de Polignac number, because 1921761 - 2⁵ = 1921729 is a prime.

It is a super-2 number, since 2×1921761² = 7386330682242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1921763) 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, 991 + ... + 2196.

2^1921761 is an apocalyptic number.

It is an amenable number.

1921761 is a deficient number, since it is larger than the sum of its proper divisors (896431).

1921761 is a wasteful number, since it uses less digits than its factorization.

1921761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3260 (or 3257 counting only the distinct ones).

The product of its digits is 756, while the sum is 27.

The square root of 1921761 is about 1386.2759465561. The cubic root of 1921761 is about 124.3272874909.

It can be divided in two parts, 192 and 1761, that added together give a triangular number (1953 = T₆₂).

The spelling of 1921761 in words is "one million, nine hundred twenty-one thousand, seven hundred sixty-one".