64061891 has 2 divisors, whose sum is σ = 64061892. Its totient is φ = 64061890.

The previous prime is 64061869. The next prime is 64061927. The reversal of 64061891 is 19816046.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64061891 is a prime.

It is not a weakly prime, because it can be changed into another prime (64061791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32030945 + 32030946.

It is an arithmetic number, because the mean of its divisors is an integer number (32030946).

Almost surely, 2^64061891 is an apocalyptic number.

64061891 is a deficient number, since it is larger than the sum of its proper divisors (1).

64061891 is an equidigital number, since it uses as much as digits as its factorization.

64061891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 64061891 is about 8003.8672527722. The cubic root of 64061891 is about 400.1288980421.

The spelling of 64061891 in words is "sixty-four million, sixty-one thousand, eight hundred ninety-one".