1964712581 has 16 divisors (see below), whose sum is σ = 2141889456. Its totient is φ = 1791369216.

The previous prime is 1964712569. The next prime is 1964712611. The reversal of 1964712581 is 1852174691.

It can be written as a sum of positive squares in 8 ways, for example, as 1378636900 + 586075681 = 37130^2 + 24209^2 .

It is not a de Polignac number, because 1964712581 - 2⁶ = 1964712517 is a prime.

It is a super-2 number, since 2×1964712581² = 7720191051879363122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1964712181) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 457661 + ... + 461933.

It is an arithmetic number, because the mean of its divisors is an integer number (133868091).

Almost surely, 2^1964712581 is an apocalyptic number.

It is an amenable number.

1964712581 is a deficient number, since it is larger than the sum of its proper divisors (177176875).

1964712581 is a wasteful number, since it uses less digits than its factorization.

1964712581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4712.

The product of its digits is 120960, while the sum is 44.

The square root of 1964712581 is about 44325.0784658076. The cubic root of 1964712581 is about 1252.4671446343.

The spelling of 1964712581 in words is "one billion, nine hundred sixty-four million, seven hundred twelve thousand, five hundred eighty-one".