645666414 has 16 divisors (see below), whose sum is σ = 1321364352. Its totient is φ = 210216888.

The previous prime is 645666389. The next prime is 645666421. The reversal of 645666414 is 414666546.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1251034 + ... + 1251549.

It is an arithmetic number, because the mean of its divisors is an integer number (82585272).

Almost surely, 2^645666414 is an apocalyptic number.

645666414 is an abundant number, since it is smaller than the sum of its proper divisors (675697938).

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

645666414 is a wasteful number, since it uses less digits than its factorization.

645666414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2502631.

The product of its digits is 414720, while the sum is 42.

The square root of 645666414 is about 25409.9668240633. The cubic root of 645666414 is about 864.3097231705.

The spelling of 645666414 in words is "six hundred forty-five million, six hundred sixty-six thousand, four hundred fourteen".