64721037 has 4 divisors (see below), whose sum is σ = 86294720. Its totient is φ = 43147356.

The previous prime is 64721009. The next prime is 64721047. The reversal of 64721037 is 73012746.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 64721037 - 2¹⁶ = 64655501 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64720995 and 64721013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64721047) 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, 10786837 + ... + 10786842.

It is an arithmetic number, because the mean of its divisors is an integer number (21573680).

Almost surely, 2^64721037 is an apocalyptic number.

It is an amenable number.

64721037 is a deficient number, since it is larger than the sum of its proper divisors (21573683).

64721037 is a wasteful number, since it uses less digits than its factorization.

64721037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21573682.

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 64721037 is about 8044.9385951665. The cubic root of 64721037 is about 401.4965542472.

The spelling of 64721037 in words is "sixty-four million, seven hundred twenty-one thousand, thirty-seven".