64717720 has 16 divisors (see below), whose sum is σ = 145614960. Its totient is φ = 25887072.

The previous prime is 64717687. The next prime is 64717727. The reversal of 64717720 is 2771746.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64717727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 808932 + ... + 809011.

It is an arithmetic number, because the mean of its divisors is an integer number (9100935).

Almost surely, 2^64717720 is an apocalyptic number.

It is an amenable number.

64717720 is an abundant number, since it is smaller than the sum of its proper divisors (80897240).

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

64717720 is a wasteful number, since it uses less digits than its factorization.

64717720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1617954 (or 1617950 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 34.

The square root of 64717720 is about 8044.7324380616. The cubic root of 64717720 is about 401.4896951337.

The spelling of 64717720 in words is "sixty-four million, seven hundred seventeen thousand, seven hundred twenty".