64123521 has 32 divisors (see below), whose sum is σ = 107827200. Its totient is φ = 32926080.

The previous prime is 64123513. The next prime is 64123529. The reversal of 64123521 is 12532146.

It is an interprime number because it is at equal distance from previous prime (64123513) and next prime (64123529).

It is not a de Polignac number, because 64123521 - 2³ = 64123513 is a prime.

It is a super-2 number, since 2×64123521² = 8223651890874882, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 64123491 and 64123500.

It is not an unprimeable number, because it can be changed into a prime (64123529) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19000 + ... + 22118.

It is an arithmetic number, because the mean of its divisors is an integer number (3369600).

Almost surely, 2^64123521 is an apocalyptic number.

It is an amenable number.

64123521 is a deficient number, since it is larger than the sum of its proper divisors (43703679).

64123521 is a wasteful number, since it uses less digits than its factorization.

64123521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3229.

The product of its digits is 1440, while the sum is 24.

The square root of 64123521 is about 8007.7163411300. The cubic root of 64123521 is about 400.2571700402.

Adding to 64123521 its reverse (12532146), we get a palindrome (76655667).

The spelling of 64123521 in words is "sixty-four million, one hundred twenty-three thousand, five hundred twenty-one".