1664622356 has 6 divisors (see below), whose sum is σ = 2913089130. Its totient is φ = 832311176.

The previous prime is 1664622347. The next prime is 1664622367. The reversal of 1664622356 is 6532264661.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1661866756 + 2755600 = 40766^2 + 1660^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 208077791 + ... + 208077798.

It is an arithmetic number, because the mean of its divisors is an integer number (485514855).

Almost surely, 2^1664622356 is an apocalyptic number.

It is an amenable number.

1664622356 is a deficient number, since it is larger than the sum of its proper divisors (1248466774).

1664622356 is a wasteful number, since it uses less digits than its factorization.

1664622356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416155593 (or 416155591 counting only the distinct ones).

The product of its digits is 311040, while the sum is 41.

The square root of 1664622356 is about 40799.7837739368. The cubic root of 1664622356 is about 1185.1461435001.

The spelling of 1664622356 in words is "one billion, six hundred sixty-four million, six hundred twenty-two thousand, three hundred fifty-six".