693939021 has 4 divisors (see below), whose sum is σ = 925252032. Its totient is φ = 462626012.

The previous prime is 693939011. The next prime is 693939023. The reversal of 693939021 is 120939396.

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 693939021 - 2⁷ = 693938893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (693939023) 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, 115656501 + ... + 115656506.

It is an arithmetic number, because the mean of its divisors is an integer number (231313008).

Almost surely, 2^693939021 is an apocalyptic number.

It is an amenable number.

693939021 is a deficient number, since it is larger than the sum of its proper divisors (231313011).

693939021 is a wasteful number, since it uses less digits than its factorization.

693939021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231313010.

The product of its (nonzero) digits is 78732, while the sum is 42.

The square root of 693939021 is about 26342.7223536217. The cubic root of 693939021 is about 885.3339184892. Note that the first 3 decimals are identical.

The spelling of 693939021 in words is "six hundred ninety-three million, nine hundred thirty-nine thousand, twenty-one".