64409437 has 4 divisors (see below), whose sum is σ = 64425820. Its totient is φ = 64393056.

The previous prime is 64409381. The next prime is 64409459. The reversal of 64409437 is 73490446.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 73490446 = 2 ⋅36745223.

It can be written as a sum of positive squares in 2 ways, for example, as 42263001 + 22146436 = 6501^2 + 4706^2 .

It is a 3-Lehmer number, since φ(64409437) divides (64409437-1)³.

It is a cyclic number.

It is not a de Polignac number, because 64409437 - 2⁷ = 64409309 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64409396 and 64409405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64409467) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1639 + ... + 11467.

It is an arithmetic number, because the mean of its divisors is an integer number (16106455).

Almost surely, 2^64409437 is an apocalyptic number.

64409437 is the 6553-rd pentagonal number.

It is an amenable number.

64409437 is a deficient number, since it is larger than the sum of its proper divisors (16383).

64409437 is an equidigital number, since it uses as much as digits as its factorization.

64409437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16382.

The product of its (nonzero) digits is 72576, while the sum is 37.

The square root of 64409437 is about 8025.5490154880. The cubic root of 64409437 is about 400.8511811917.

It can be divided in two parts, 64409 and 437, that added together give a palindrome (64846).

The spelling of 64409437 in words is "sixty-four million, four hundred nine thousand, four hundred thirty-seven".