645980735 has 8 divisors (see below), whose sum is σ = 777074640. Its totient is φ = 515519424.

The previous prime is 645980729. The next prime is 645980747. The reversal of 645980735 is 537089546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645980735 - 2⁴ = 645980719 is a prime.

It is a super-2 number, since 2×645980735² = 834582219982280450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 645980735.

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, 155897 + ... + 159986.

It is an arithmetic number, because the mean of its divisors is an integer number (97134330).

Almost surely, 2^645980735 is an apocalyptic number.

645980735 is a deficient number, since it is larger than the sum of its proper divisors (131093905).

645980735 is a wasteful number, since it uses less digits than its factorization.

645980735 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316297.

The product of its (nonzero) digits is 907200, while the sum is 47.

The square root of 645980735 is about 25416.1510658085. The cubic root of 645980735 is about 864.4499538005.

It can be divided in two parts, 6459 and 80735, that multiplied together give a triangular number (521467365 = T₃₂₂₉₄).

The spelling of 645980735 in words is "six hundred forty-five million, nine hundred eighty thousand, seven hundred thirty-five".