64220815 has 8 divisors (see below), whose sum is σ = 81598320. Its totient is φ = 48354432.

The previous prime is 64220813. The next prime is 64220833. The reversal of 64220815 is 51802246.

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 64220815 - 2¹ = 64220813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64220813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 377685 + ... + 377854.

It is an arithmetic number, because the mean of its divisors is an integer number (10199790).

Almost surely, 2^64220815 is an apocalyptic number.

64220815 is a deficient number, since it is larger than the sum of its proper divisors (17377505).

64220815 is a wasteful number, since it uses less digits than its factorization.

64220815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755561.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 64220815 is about 8013.7890538746. The cubic root of 64220815 is about 400.4595031899.

The spelling of 64220815 in words is "sixty-four million, two hundred twenty thousand, eight hundred fifteen".