445540640 has 24 divisors (see below), whose sum is σ = 1052590140. Its totient is φ = 178216192.

The previous prime is 445540621. The next prime is 445540679. The reversal of 445540640 is 46045544.

It can be written as a sum of positive squares in 2 ways, for example, as 417957136 + 27583504 = 20444^2 + 5252^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 445540597 and 445540606.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1392155 + ... + 1392474.

Almost surely, 2^445540640 is an apocalyptic number.

445540640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

445540640 is an abundant number, since it is smaller than the sum of its proper divisors (607049500).

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

445540640 is a wasteful number, since it uses less digits than its factorization.

445540640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2784644 (or 2784636 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 32.

The square root of 445540640 is about 21107.8336169300. The cubic root of 445540640 is about 763.7697285796.

The spelling of 445540640 in words is "four hundred forty-five million, five hundred forty thousand, six hundred forty".