1964123581 has 8 divisors (see below), whose sum is σ = 2245568960. Its totient is φ = 1682892288.

The previous prime is 1964123569. The next prime is 1964123597. The reversal of 1964123581 is 1853214691.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1964123581 - 2¹⁷ = 1963992509 is a prime.

It is a super-2 number, since 2×1964123581² = 7715562882880527122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1964123501) 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, 33351 + ... + 70996.

It is an arithmetic number, because the mean of its divisors is an integer number (280696120).

Almost surely, 2^1964123581 is an apocalyptic number.

It is an amenable number.

1964123581 is a deficient number, since it is larger than the sum of its proper divisors (281445379).

1964123581 is a wasteful number, since it uses less digits than its factorization.

1964123581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107043.

The product of its digits is 51840, while the sum is 40.

The square root of 1964123581 is about 44318.4338735023. The cubic root of 1964123581 is about 1252.3419733350.

The spelling of 1964123581 in words is "one billion, nine hundred sixty-four million, one hundred twenty-three thousand, five hundred eighty-one".