1721992 has 8 divisors (see below), whose sum is σ = 3228750. Its totient is φ = 860992.

The previous prime is 1721983. The next prime is 1722013. The reversal of 1721992 is 2991271.

It can be written as a sum of positive squares in only one way, i.e., 1153476 + 568516 = 1074^2 + 754^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a nialpdrome in base 8.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107617 + ... + 107632.

2^1721992 is an apocalyptic number.

It is an amenable number.

1721992 is a deficient number, since it is larger than the sum of its proper divisors (1506758).

1721992 is a wasteful number, since it uses less digits than its factorization.

1721992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215255 (or 215251 counting only the distinct ones).

The product of its digits is 2268, while the sum is 31.

The square root of 1721992 is about 1312.2469279827. The cubic root of 1721992 is about 119.8607644339.

The spelling of 1721992 in words is "one million, seven hundred twenty-one thousand, nine hundred ninety-two".