661293258 has 16 divisors (see below), whose sum is σ = 1335682656. Its totient is φ = 218248400.

The previous prime is 661293221. The next prime is 661293301. The reversal of 661293258 is 852392166.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 545016 + ... + 546227.

It is an arithmetic number, because the mean of its divisors is an integer number (83480166).

Almost surely, 2^661293258 is an apocalyptic number.

661293258 is an abundant number, since it is smaller than the sum of its proper divisors (674389398).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661293258 is a wasteful number, since it uses less digits than its factorization.

661293258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1091349.

The product of its digits is 155520, while the sum is 42.

The square root of 661293258 is about 25715.6228390448. The cubic root of 661293258 is about 871.2270780911.

The spelling of 661293258 in words is "six hundred sixty-one million, two hundred ninety-three thousand, two hundred fifty-eight".