1993657 has 2 divisors, whose sum is σ = 1993658. Its totient is φ = 1993656.

The previous prime is 1993643. The next prime is 1993661. The reversal of 1993657 is 7563991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1212201 + 781456 = 1101^2 + 884^2 .

It is a cyclic number.

It is not a de Polignac number, because 1993657 - 2⁷ = 1993529 is a prime.

1993657 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (1993627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 996828 + 996829.

It is an arithmetic number, because the mean of its divisors is an integer number (996829).

2^1993657 is an apocalyptic number.

It is an amenable number.

1993657 is a deficient number, since it is larger than the sum of its proper divisors (1).

1993657 is an equidigital number, since it uses as much as digits as its factorization.

1993657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51030, while the sum is 40.

The square root of 1993657 is about 1411.9691922985. The cubic root of 1993657 is about 125.8587692783.

The spelling of 1993657 in words is "one million, nine hundred ninety-three thousand, six hundred fifty-seven".