64201662721 has 16 divisors (see below), whose sum is σ = 73869264000. Its totient is φ = 54658666368.

The previous prime is 64201662709. The next prime is 64201662751. The reversal of 64201662721 is 12726610246.

64201662721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 64201662721 - 2¹³ = 64201654529 is a prime.

It is a super-2 number, since 2×64201662721² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64201662751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1245070 + ... + 1295608.

It is an arithmetic number, because the mean of its divisors is an integer number (4616829000).

Almost surely, 2^64201662721 is an apocalyptic number.

It is an amenable number.

64201662721 is a deficient number, since it is larger than the sum of its proper divisors (9667601279).

64201662721 is a wasteful number, since it uses less digits than its factorization.

64201662721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51768.

The product of its (nonzero) digits is 48384, while the sum is 37.

The spelling of 64201662721 in words is "sixty-four billion, two hundred one million, six hundred sixty-two thousand, seven hundred twenty-one".