1961758656 has 448 divisors, whose sum is σ = 7189378560. Its totient is φ = 515358720.

The previous prime is 1961758649. The next prime is 1961758661. The reversal of 1961758656 is 6568571691.

1961758656 is a `hidden beast` number, since 1 + 9 + 6 + 1 + 7 + 586 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4200535 + ... + 4201001.

It is an arithmetic number, because the mean of its divisors is an integer number (16047720).

Almost surely, 2^1961758656 is an apocalyptic number.

1961758656 is a gapful number since it is divisible by the number (16) 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 1961758656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3594689280).

1961758656 is an abundant number, since it is smaller than the sum of its proper divisors (5227619904).

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

1961758656 is a wasteful number, since it uses less digits than its factorization.

1961758656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529 (or 513 counting only the distinct ones).

The product of its digits is 2721600, while the sum is 54.

The square root of 1961758656 is about 44291.7447838759. The cubic root of 1961758656 is about 1251.8391393394.

The spelling of 1961758656 in words is "one billion, nine hundred sixty-one million, seven hundred fifty-eight thousand, six hundred fifty-six".