64642207 has 4 divisors (see below), whose sum is σ = 73876816. Its totient is φ = 55407600.

The previous prime is 64642181. The next prime is 64642241. The reversal of 64642207 is 70224646.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64642207 is a prime.

It is a super-2 number, since 2×64642207² = 8357229851661698, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64642267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4617294 + ... + 4617307.

It is an arithmetic number, because the mean of its divisors is an integer number (18469204).

Almost surely, 2^64642207 is an apocalyptic number.

64642207 is a deficient number, since it is larger than the sum of its proper divisors (9234609).

64642207 is an equidigital number, since it uses as much as digits as its factorization.

64642207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9234608.

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 64642207 is about 8040.0377486676. The cubic root of 64642207 is about 401.3334808819. Note that the first 3 decimals are identical.

The spelling of 64642207 in words is "sixty-four million, six hundred forty-two thousand, two hundred seven".