1961287020 has 336 divisors, whose sum is σ = 7703394048. Its totient is φ = 407306880.

The previous prime is 1961287001. The next prime is 1961287021. The reversal of 1961287020 is 207821691.

1961287020 is a `hidden beast` number, since 19 + 612 + 8 + 7 + 0 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961287021) by changing a digit.

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 111 ways as a sum of consecutive naturals, for example, 1121787 + ... + 1123533.

It is an arithmetic number, because the mean of its divisors is an integer number (22926768).

Almost surely, 2^1961287020 is an apocalyptic number.

1961287020 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 1961287020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3851697024).

1961287020 is an abundant number, since it is smaller than the sum of its proper divisors (5742107028).

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

1961287020 is a wasteful number, since it uses less digits than its factorization.

1961287020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1792 (or 1775 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 1961287020 is about 44286.4202662622. The cubic root of 1961287020 is about 1251.7388110407.

The spelling of 1961287020 in words is "one billion, nine hundred sixty-one million, two hundred eighty-seven thousand, twenty".