1664350425 has 18 divisors (see below), whose sum is σ = 2981036942. Its totient is φ = 887653440.

The previous prime is 1664350421. The next prime is 1664350427. The reversal of 1664350425 is 5240534661.

1664350425 is a `hidden beast` number, since 1 + 6 + 643 + 5 + 0 + 4 + 2 + 5 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 22155849 + 1642194576 = 4707^2 + 40524^2 .

It is not a de Polignac number, because 1664350425 - 2² = 1664350421 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1664350425.

It is not an unprimeable number, because it can be changed into a prime (1664350421) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3698332 + ... + 3698781.

Almost surely, 2^1664350425 is an apocalyptic number.

1664350425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1664350425 is a deficient number, since it is larger than the sum of its proper divisors (1316686517).

1664350425 is a wasteful number, since it uses less digits than its factorization.

1664350425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7397129 (or 7397121 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 1664350425 is about 40796.4511324208. The cubic root of 1664350425 is about 1185.0816052331.

The spelling of 1664350425 in words is "one billion, six hundred sixty-four million, three hundred fifty thousand, four hundred twenty-five".