64521629 has 4 divisors (see below), whose sum is σ = 66022176. Its totient is φ = 63021084.

The previous prime is 64521623. The next prime is 64521641. The reversal of 64521629 is 92612546.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64521629 - 2²⁴ = 47744413 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64521623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 750209 + ... + 750294.

It is an arithmetic number, because the mean of its divisors is an integer number (16505544).

Almost surely, 2^64521629 is an apocalyptic number.

It is an amenable number.

64521629 is a deficient number, since it is larger than the sum of its proper divisors (1500547).

64521629 is a wasteful number, since it uses less digits than its factorization.

64521629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500546.

The product of its digits is 25920, while the sum is 35.

The square root of 64521629 is about 8032.5356519595. The cubic root of 64521629 is about 401.0837879405.

The spelling of 64521629 in words is "sixty-four million, five hundred twenty-one thousand, six hundred twenty-nine".