64210661 has 4 divisors (see below), whose sum is σ = 64455072. Its totient is φ = 63966252.

The previous prime is 64210639. The next prime is 64210673. The reversal of 64210661 is 16601246.

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 64210661 - 2¹⁸ = 63948517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64210661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64210681) 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, 121811 + ... + 122336.

It is an arithmetic number, because the mean of its divisors is an integer number (16113768).

Almost surely, 2^64210661 is an apocalyptic number.

It is an amenable number.

64210661 is a deficient number, since it is larger than the sum of its proper divisors (244411).

64210661 is a wasteful number, since it uses less digits than its factorization.

64210661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244410.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 64210661 is about 8013.1554958081. The cubic root of 64210661 is about 400.4383964292.

The spelling of 64210661 in words is "sixty-four million, two hundred ten thousand, six hundred sixty-one".