1721866772 has 12 divisors (see below), whose sum is σ = 3013570560. Its totient is φ = 860846616.

The previous prime is 1721866763. The next prime is 1721866781. The reversal of 1721866772 is 2776681271.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1721866763) and next prime (1721866781).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47423 + ... + 75449.

It is an arithmetic number, because the mean of its divisors is an integer number (251130880).

Almost surely, 2^1721866772 is an apocalyptic number.

It is an amenable number.

1721866772 is a deficient number, since it is larger than the sum of its proper divisors (1291703788).

1721866772 is a wasteful number, since it uses less digits than its factorization.

1721866772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43390 (or 43388 counting only the distinct ones).

The product of its digits is 395136, while the sum is 47.

The square root of 1721866772 is about 41495.3825383018. The cubic root of 1721866772 is about 1198.5785882850.

The spelling of 1721866772 in words is "one billion, seven hundred twenty-one million, eight hundred sixty-six thousand, seven hundred seventy-two".