863670021 has 8 divisors (see below), whose sum is σ = 1182683424. Its totient is φ = 560218320.

The previous prime is 863670001. The next prime is 863670077. The reversal of 863670021 is 120076368.

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

It is not a de Polignac number, because 863670021 - 2¹⁵ = 863637253 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (863670001) 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, 3890295 + ... + 3890516.

It is an arithmetic number, because the mean of its divisors is an integer number (147835428).

Almost surely, 2^863670021 is an apocalyptic number.

It is an amenable number.

863670021 is a deficient number, since it is larger than the sum of its proper divisors (319013403).

863670021 is a wasteful number, since it uses less digits than its factorization.

863670021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7780851.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 863670021 is about 29388.2633205843. The cubic root of 863670021 is about 952.3193636554.

The spelling of 863670021 in words is "eight hundred sixty-three million, six hundred seventy thousand, twenty-one".