661040554 has 8 divisors (see below), whose sum is σ = 992042208. Its totient is φ = 330359820.

The previous prime is 661040531. The next prime is 661040579. The reversal of 661040554 is 455040166.

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

It is a super-2 number, since 2×661040554² = 873949228065253832, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75012 + ... + 83359.

It is an arithmetic number, because the mean of its divisors is an integer number (124005276).

Almost surely, 2^661040554 is an apocalyptic number.

661040554 is a deficient number, since it is larger than the sum of its proper divisors (331001654).

661040554 is a wasteful number, since it uses less digits than its factorization.

661040554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160460.

The product of its (nonzero) digits is 14400, while the sum is 31.

The square root of 661040554 is about 25710.7089361612. The cubic root of 661040554 is about 871.1160881912.

The spelling of 661040554 in words is "six hundred sixty-one million, forty thousand, five hundred fifty-four".