1673676821 has 2 divisors, whose sum is σ = 1673676822. Its totient is φ = 1673676820.

The previous prime is 1673676799. The next prime is 1673676827. The reversal of 1673676821 is 1286763761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1450771921 + 222904900 = 38089^2 + 14930^2 .

It is a cyclic number.

It is not a de Polignac number, because 1673676821 - 2²² = 1669482517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1673676827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 836838410 + 836838411.

It is an arithmetic number, because the mean of its divisors is an integer number (836838411).

Almost surely, 2^1673676821 is an apocalyptic number.

It is an amenable number.

1673676821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1673676821 is an equidigital number, since it uses as much as digits as its factorization.

1673676821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 47.

The square root of 1673676821 is about 40910.5954613227. The cubic root of 1673676821 is about 1187.2910677443.

The spelling of 1673676821 in words is "one billion, six hundred seventy-three million, six hundred seventy-six thousand, eight hundred twenty-one".