866444042501 has 4 divisors (see below), whose sum is σ = 866446613472. Its totient is φ = 866441471532.

The previous prime is 866444042483. The next prime is 866444042539. The reversal of 866444042501 is 105240444668.

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 866444042501 - 2¹⁴ = 866444026117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866444042201) 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, 687131 + ... + 1484936.

It is an arithmetic number, because the mean of its divisors is an integer number (216611653368).

Almost surely, 2^866444042501 is an apocalyptic number.

It is an amenable number.

866444042501 is a deficient number, since it is larger than the sum of its proper divisors (2570971).

866444042501 is a wasteful number, since it uses less digits than its factorization.

866444042501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2570970.

The product of its (nonzero) digits is 737280, while the sum is 44.

The spelling of 866444042501 in words is "eight hundred sixty-six billion, four hundred forty-four million, forty-two thousand, five hundred one".