64137661 has 16 divisors (see below), whose sum is σ = 75358080. Its totient is φ = 53452800.

The previous prime is 64137643. The next prime is 64137683. The reversal of 64137661 is 16673146.

64137661 = T₂₄₆₁ + T₂₄₆₂ + ... + T₂₄₈₁.

It is a cyclic number.

It is not a de Polignac number, because 64137661 - 2⁷ = 64137533 is a prime.

It is a super-2 number, since 2×64137661² = 8227279117101842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64132661) 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, 39261 + ... + 40861.

It is an arithmetic number, because the mean of its divisors is an integer number (4709880).

Almost surely, 2^64137661 is an apocalyptic number.

It is an amenable number.

64137661 is a deficient number, since it is larger than the sum of its proper divisors (11220419).

64137661 is a wasteful number, since it uses less digits than its factorization.

64137661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1764.

The product of its digits is 18144, while the sum is 34.

The square root of 64137661 is about 8008.5991908698. The cubic root of 64137661 is about 400.2865883687.

The spelling of 64137661 in words is "sixty-four million, one hundred thirty-seven thousand, six hundred sixty-one".