690158221 has 4 divisors (see below), whose sum is σ = 690329500. Its totient is φ = 689986944.

The previous prime is 690158191. The next prime is 690158233. The reversal of 690158221 is 122851096.

690158221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 149084100 + 541074121 = 12210^2 + 23261^2 .

It is a cyclic number.

It is not a de Polignac number, because 690158221 - 2⁷ = 690158093 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 (690158281) 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, 79446 + ... + 87703.

It is an arithmetic number, because the mean of its divisors is an integer number (172582375).

Almost surely, 2^690158221 is an apocalyptic number.

It is an amenable number.

690158221 is a deficient number, since it is larger than the sum of its proper divisors (171279).

690158221 is a wasteful number, since it uses less digits than its factorization.

690158221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171278.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 690158221 is about 26270.8625857622. The cubic root of 690158221 is about 883.7231295284.

The spelling of 690158221 in words is "six hundred ninety million, one hundred fifty-eight thousand, two hundred twenty-one".