64419561 has 6 divisors (see below), whose sum is σ = 93050490. Its totient is φ = 42946368.

The previous prime is 64419559. The next prime is 64419577. The reversal of 64419561 is 16591446.

64419561 is a `hidden beast` number, since 644 + 1 + 9 + 5 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 36000000 + 28419561 = 6000^2 + 5331^2 .

It is not a de Polignac number, because 64419561 - 2¹ = 64419559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64419521) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3578856 + ... + 3578873.

It is an arithmetic number, because the mean of its divisors is an integer number (15508415).

Almost surely, 2^64419561 is an apocalyptic number.

It is an amenable number.

64419561 is a deficient number, since it is larger than the sum of its proper divisors (28630929).

64419561 is a wasteful number, since it uses less digits than its factorization.

64419561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7157735 (or 7157732 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 64419561 is about 8026.1797263704. The cubic root of 64419561 is about 400.8721822796.

It can be divided in two parts, 64419 and 561, that added together give a triangular number (64980 = T₃₆₀).

The spelling of 64419561 in words is "sixty-four million, four hundred nineteen thousand, five hundred sixty-one".