720100645 has 12 divisors (see below), whose sum is σ = 949819500. Its totient is φ = 523709120.

The previous prime is 720100621. The next prime is 720100663. The reversal of 720100645 is 546001027.

It can be written as a sum of positive squares in 2 ways, for example, as 377369476 + 342731169 = 19426^2 + 18513^2 .

It is not a de Polignac number, because 720100645 - 2⁷ = 720100517 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 594520 + ... + 595729.

It is an arithmetic number, because the mean of its divisors is an integer number (79151625).

Almost surely, 2^720100645 is an apocalyptic number.

It is an amenable number.

720100645 is a deficient number, since it is larger than the sum of its proper divisors (229718855).

720100645 is a wasteful number, since it uses less digits than its factorization.

720100645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1190276 (or 1190265 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 720100645 is about 26834.6910733103. The cubic root of 720100645 is about 896.3227094935.

The spelling of 720100645 in words is "seven hundred twenty million, one hundred thousand, six hundred forty-five".