393665490 has 48 divisors (see below), whose sum is σ = 1032946200. Its totient is φ = 104011776.

The previous prime is 393665483. The next prime is 393665551. The reversal of 393665490 is 94566393.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 226713249 + 166952241 = 15057^2 + 12921^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10255 + ... + 29874.

Almost surely, 2^393665490 is an apocalyptic number.

393665490 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

393665490 is an abundant number, since it is smaller than the sum of its proper divisors (639280710).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

393665490 is a wasteful number, since it uses less digits than its factorization.

393665490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40251 (or 40248 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 45.

The square root of 393665490 is about 19841.0052668709. The cubic root of 393665490 is about 732.8961634499.

The spelling of 393665490 in words is "three hundred ninety-three million, six hundred sixty-five thousand, four hundred ninety".