661614513540 has 48 divisors (see below), whose sum is σ = 1875970279680. Its totient is φ = 174197237760.

The previous prime is 661614513457. The next prime is 661614513551. The reversal of 661614513540 is 45315416166.

It is a junction number, because it is equal to n+sod(n) for n = 661614513492 and 661614513501.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69785821 + ... + 69795300.

It is an arithmetic number, because the mean of its divisors is an integer number (39082714160).

Almost surely, 2^661614513540 is an apocalyptic number.

661614513540 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

661614513540 is an abundant number, since it is smaller than the sum of its proper divisors (1214355766140).

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

661614513540 is a wasteful number, since it uses less digits than its factorization.

661614513540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139581212 (or 139581210 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 42.

The spelling of 661614513540 in words is "six hundred sixty-one billion, six hundred fourteen million, five hundred thirteen thousand, five hundred forty".