661464480 has 384 divisors, whose sum is σ = 2362348800. Its totient is φ = 154828800.

The previous prime is 661464469. The next prime is 661464481. The reversal of 661464480 is 84464166.

It is not an unprimeable number, because it can be changed into a prime (661464481) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10843650 + ... + 10843710.

It is an arithmetic number, because the mean of its divisors is an integer number (6151950).

Almost surely, 2^661464480 is an apocalyptic number.

661464480 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 661464480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1181174400).

661464480 is an abundant number, since it is smaller than the sum of its proper divisors (1700884320).

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

661464480 is a wasteful number, since it uses less digits than its factorization.

661464480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 39.

The square root of 661464480 is about 25718.9517671308. The cubic root of 661464480 is about 871.3022642853.

The spelling of 661464480 in words is "six hundred sixty-one million, four hundred sixty-four thousand, four hundred eighty".