1664266831 has 2 divisors, whose sum is σ = 1664266832. Its totient is φ = 1664266830.

The previous prime is 1664266777. The next prime is 1664266841. The reversal of 1664266831 is 1386624661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1664266831 - 2²³ = 1655878223 is a prime.

It is a super-2 number, since 2×1664266831² = 5539568169533565122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1664266841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832133415 + 832133416.

It is an arithmetic number, because the mean of its divisors is an integer number (832133416).

Almost surely, 2^1664266831 is an apocalyptic number.

1664266831 is a deficient number, since it is larger than the sum of its proper divisors (1).

1664266831 is an equidigital number, since it uses as much as digits as its factorization.

1664266831 is an evil number, because the sum of its binary digits is even.

The product of its digits is 248832, while the sum is 43.

The square root of 1664266831 is about 40795.4265941662. The cubic root of 1664266831 is about 1185.0617641850.

The spelling of 1664266831 in words is "one billion, six hundred sixty-four million, two hundred sixty-six thousand, eight hundred thirty-one".