1662291997 has 2 divisors, whose sum is σ = 1662291998. Its totient is φ = 1662291996.

The previous prime is 1662291923. The next prime is 1662292003. The reversal of 1662291997 is 7991922661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1359323161 + 302968836 = 36869^2 + 17406^2 .

It is a cyclic number.

It is not a de Polignac number, because 1662291997 - 2¹¹ = 1662289949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1662291097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831145998 + 831145999.

It is an arithmetic number, because the mean of its divisors is an integer number (831145999).

Almost surely, 2^1662291997 is an apocalyptic number.

It is an amenable number.

1662291997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1662291997 is an equidigital number, since it uses as much as digits as its factorization.

1662291997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 734832, while the sum is 52.

The square root of 1662291997 is about 40771.2152995223. The cubic root of 1662291997 is about 1184.5928436760.

The spelling of 1662291997 in words is "one billion, six hundred sixty-two million, two hundred ninety-one thousand, nine hundred ninety-seven".