42591534435961 has 9 divisors (see below), whose sum is σ = 49545307485999. Its totient is φ = 36506990359224.

The previous prime is 42591534435959. The next prime is 42591534435973. The reversal of 42591534435961 is 16953443519524.

The square root of 42591534435961 is 6526219.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 38631259314025 + 3960275121936 = 6215405^2 + 1990044^2 .

It is not a de Polignac number, because 42591534435961 - 2¹ = 42591534435959 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 42591534435961.

It is not an unprimeable number, because it can be changed into a prime (42591534435661) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 45217375 + ... + 46149691.

It is an arithmetic number, because the mean of its divisors is an integer number (5505034165111).

Almost surely, 2^{42591534435961} is an apocalyptic number.

42591534435961 is the 6526219-th square number.

42591534435961 is the 3263110-th centered octagonal number.

It is an amenable number.

42591534435961 is a deficient number, since it is larger than the sum of its proper divisors (6953773050038).

42591534435961 is an frugal number, since it uses more digits than its factorization.

42591534435961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1864648 (or 932324 counting only the distinct ones).

The product of its digits is 69984000, while the sum is 61.

The spelling of 42591534435961 in words is "forty-two trillion, five hundred ninety-one billion, five hundred thirty-four million, four hundred thirty-five thousand, nine hundred sixty-one".