1961977836 has 192 divisors, whose sum is σ = 5910732800. Its totient is φ = 502951680.

The previous prime is 1961977807. The next prime is 1961977847. The reversal of 1961977836 is 6387791691.

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 63 ways as a sum of consecutive naturals, for example, 1979301 + ... + 1980291.

Almost surely, 2^1961977836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1961977836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2955366400).

1961977836 is an abundant number, since it is smaller than the sum of its proper divisors (3948754964).

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

1961977836 is a wasteful number, since it uses less digits than its factorization.

1961977836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069 (or 1053 counting only the distinct ones).

The product of its digits is 3429216, while the sum is 57.

The square root of 1961977836 is about 44294.2189907442. The cubic root of 1961977836 is about 1251.8857587140.

The spelling of 1961977836 in words is "one billion, nine hundred sixty-one million, nine hundred seventy-seven thousand, eight hundred thirty-six".