1961166820 has 48 divisors (see below), whose sum is σ = 4145541120. Its totient is φ = 779328896.

The previous prime is 1961166811. The next prime is 1961166853. The reversal of 1961166820 is 286611691.

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, 3852726 + ... + 3853234.

It is an arithmetic number, because the mean of its divisors is an integer number (86365440).

Almost surely, 2^1961166820 is an apocalyptic number.

1961166820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1961166820 is an abundant number, since it is smaller than the sum of its proper divisors (2184374300).

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

1961166820 is a wasteful number, since it uses less digits than its factorization.

1961166820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1404 (or 1402 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 40.

The square root of 1961166820 is about 44285.0631703287. The cubic root of 1961166820 is about 1251.7132390435.

The spelling of 1961166820 in words is "one billion, nine hundred sixty-one million, one hundred sixty-six thousand, eight hundred twenty".