690438457 has 4 divisors (see below), whose sum is σ = 690992500. Its totient is φ = 689884416.

The previous prime is 690438431. The next prime is 690438461. The reversal of 690438457 is 754834096.

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 370601001 + 319837456 = 19251^2 + 17884^2 .

It is a cyclic number.

It is not a de Polignac number, because 690438457 - 2¹⁵ = 690405689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (690438157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 275148 + ... + 277645.

It is an arithmetic number, because the mean of its divisors is an integer number (172748125).

Almost surely, 2^690438457 is an apocalyptic number.

It is an amenable number.

690438457 is a deficient number, since it is larger than the sum of its proper divisors (554043).

690438457 is a wasteful number, since it uses less digits than its factorization.

690438457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554042.

The product of its (nonzero) digits is 725760, while the sum is 46.

The square root of 690438457 is about 26276.1956340715. The cubic root of 690438457 is about 883.8427240966.

The spelling of 690438457 in words is "six hundred ninety million, four hundred thirty-eight thousand, four hundred fifty-seven".