661077450000 has 1800 divisors, whose sum is σ = 2806037277120. Its totient is φ = 149688000000.

The previous prime is 661077449993. The next prime is 661077450017. The reversal of 661077450000 is 54770166.

It is a tau number, because it is divible by the number of its divisors (1800).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 9310949965 + ... + 9310950035.

Almost surely, 2^661077450000 is an apocalyptic number.

661077450000 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661077450000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1403018638560).

661077450000 is an abundant number, since it is smaller than the sum of its proper divisors (2144959827120).

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

661077450000 is a wasteful number, since it uses less digits than its factorization.

661077450000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The spelling of 661077450000 in words is "six hundred sixty-one billion, seventy-seven million, four hundred fifty thousand".