64509261 has 8 divisors (see below), whose sum is σ = 86528064. Its totient is φ = 42748320.

The previous prime is 64509257. The next prime is 64509281. The reversal of 64509261 is 16290546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64509261 - 2² = 64509257 is a prime.

It is a super-2 number, since 2×64509261² = 8322889509532242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64509281) 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, 63880 + ... + 64881.

It is an arithmetic number, because the mean of its divisors is an integer number (10816008).

Almost surely, 2^64509261 is an apocalyptic number.

It is an amenable number.

64509261 is a deficient number, since it is larger than the sum of its proper divisors (22018803).

64509261 is a wasteful number, since it uses less digits than its factorization.

64509261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128931.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 64509261 is about 8031.7657460860. The cubic root of 64509261 is about 401.0581586987.

The spelling of 64509261 in words is "sixty-four million, five hundred nine thousand, two hundred sixty-one".