1961656320 has 256 divisors, whose sum is σ = 6782086080. Its totient is φ = 481296384.

The previous prime is 1961656303. The next prime is 1961656331. The reversal of 1961656320 is 236561691.

1961656320 = 273² + 274² + ... + 1807².

It is a tau number, because it is divible by the number of its divisors (256).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

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, 6389607 + ... + 6389913.

Almost surely, 2^1961656320 is an apocalyptic number.

1961656320 is a gapful number since it is divisible by the number (10) 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 1961656320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3391043040).

1961656320 is an abundant number, since it is smaller than the sum of its proper divisors (4820429760).

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

1961656320 is an equidigital number, since it uses as much as digits as its factorization.

1961656320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358 (or 330 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 1961656320 is about 44290.5895196711. The cubic root of 1961656320 is about 1251.8173713818.

The spelling of 1961656320 in words is "one billion, nine hundred sixty-one million, six hundred fifty-six thousand, three hundred twenty".