661340031314405 has 32 divisors (see below), whose sum is σ = 832639949826048. Its totient is φ = 503777352332800.

The previous prime is 661340031314357. The next prime is 661340031314411. The reversal of 661340031314405 is 504413130043166.

It is a de Polignac number, because none of the positive numbers 2^k-661340031314405 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 157267319 + ... + 161417748.

It is an arithmetic number, because the mean of its divisors is an integer number (26019998432064).

Almost surely, 2^{661340031314405} is an apocalyptic number.

It is an amenable number.

661340031314405 is a deficient number, since it is larger than the sum of its proper divisors (171299918511643).

661340031314405 is a wasteful number, since it uses less digits than its factorization.

661340031314405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318685357.

The product of its (nonzero) digits is 311040, while the sum is 41.

The spelling of 661340031314405 in words is "six hundred sixty-one trillion, three hundred forty billion, thirty-one million, three hundred fourteen thousand, four hundred five".