1961580815 has 4 divisors (see below), whose sum is σ = 2353896984. Its totient is φ = 1569264648.

The previous prime is 1961580791. The next prime is 1961580821. The reversal of 1961580815 is 5180851691.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5180851691 = 17491 ⋅296201.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1961580815 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196158077 + ... + 196158086.

It is an arithmetic number, because the mean of its divisors is an integer number (588474246).

Almost surely, 2^1961580815 is an apocalyptic number.

1961580815 is a deficient number, since it is larger than the sum of its proper divisors (392316169).

1961580815 is an equidigital number, since it uses as much as digits as its factorization.

1961580815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392316168.

The product of its (nonzero) digits is 86400, while the sum is 44.

The square root of 1961580815 is about 44289.7371294976. The cubic root of 1961580815 is about 1251.8013101784.

The spelling of 1961580815 in words is "one billion, nine hundred sixty-one million, five hundred eighty thousand, eight hundred fifteen".