1961745820 has 24 divisors (see below), whose sum is σ = 4336491600. Its totient is φ = 743398272.

The previous prime is 1961745817. The next prime is 1961745823. The reversal of 1961745820 is 285471691.

It is an interprime number because it is at equal distance from previous prime (1961745817) and next prime (1961745823).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961745823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2580865 + ... + 2581624.

It is an arithmetic number, because the mean of its divisors is an integer number (180687150).

Almost surely, 2^1961745820 is an apocalyptic number.

1961745820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1961745820 is an abundant number, since it is smaller than the sum of its proper divisors (2374745780).

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

1961745820 is a wasteful number, since it uses less digits than its factorization.

1961745820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5162517 (or 5162515 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 43.

The square root of 1961745820 is about 44291.5998807900. The cubic root of 1961745820 is about 1251.8364090270.

The spelling of 1961745820 in words is "one billion, nine hundred sixty-one million, seven hundred forty-five thousand, eight hundred twenty".