661001551139 has 16 divisors (see below), whose sum is σ = 674926668000. Its totient is φ = 647172470784.

The previous prime is 661001551097. The next prime is 661001551151. The reversal of 661001551139 is 931155100166.

It is a cyclic number.

It is not a de Polignac number, because 661001551139 - 2³² = 656706583843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661001559139) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14733089 + ... + 14777885.

It is an arithmetic number, because the mean of its divisors is an integer number (42182916750).

Almost surely, 2^661001551139 is an apocalyptic number.

661001551139 is a deficient number, since it is larger than the sum of its proper divisors (13925116861).

661001551139 is a wasteful number, since it uses less digits than its factorization.

661001551139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45862.

The product of its (nonzero) digits is 24300, while the sum is 38.

The spelling of 661001551139 in words is "six hundred sixty-one billion, one million, five hundred fifty-one thousand, one hundred thirty-nine".