1961537566 has 16 divisors (see below), whose sum is σ = 3081581568. Its totient is φ = 934659000.

The previous prime is 1961537549. The next prime is 1961537569. The reversal of 1961537566 is 6657351691.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961537569) 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, 66210 + ... + 91141.

It is an arithmetic number, because the mean of its divisors is an integer number (192598848).

Almost surely, 2^1961537566 is an apocalyptic number.

1961537566 is a deficient number, since it is larger than the sum of its proper divisors (1120044002).

1961537566 is a wasteful number, since it uses less digits than its factorization.

1961537566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157647.

The product of its digits is 1020600, while the sum is 49.

The square root of 1961537566 is about 44289.2488759970. The cubic root of 1961537566 is about 1251.7921101916.

The spelling of 1961537566 in words is "one billion, nine hundred sixty-one million, five hundred thirty-seven thousand, five hundred sixty-six".