658649381 has 8 divisors (see below), whose sum is σ = 716339064. Its totient is φ = 601963200.

The previous prime is 658649359. The next prime is 658649393. The reversal of 658649381 is 183946856.

It can be written as a sum of positive squares in 4 ways, for example, as 171741025 + 486908356 = 13105^2 + 22066^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-658649381 is a prime.

It is a super-2 number, since 2×658649381² = 867638014183366322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (658649311) 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, 249506 + ... + 252131.

It is an arithmetic number, because the mean of its divisors is an integer number (89542383).

Almost surely, 2^658649381 is an apocalyptic number.

It is an amenable number.

658649381 is a deficient number, since it is larger than the sum of its proper divisors (57689683).

658649381 is a wasteful number, since it uses less digits than its factorization.

658649381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501751.

The product of its digits is 1244160, while the sum is 50.

The square root of 658649381 is about 25664.1653088504. The cubic root of 658649381 is about 870.0644603668.

The spelling of 658649381 in words is "six hundred fifty-eight million, six hundred forty-nine thousand, three hundred eighty-one".