64499661 has 24 divisors (see below), whose sum is σ = 99432320. Its totient is φ = 40170816.

The previous prime is 64499657. The next prime is 64499663. The reversal of 64499661 is 16699446.

It is not a de Polignac number, because 64499661 - 2² = 64499657 is a prime.

It is a super-2 number, since 2×64499661² = 8320412538229842, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64499663) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9900 + ... + 15066.

Almost surely, 2^64499661 is an apocalyptic number.

It is an amenable number.

64499661 is a deficient number, since it is larger than the sum of its proper divisors (34932659).

64499661 is a wasteful number, since it uses less digits than its factorization.

64499661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5265 (or 5262 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 64499661 is about 8031.1680968586. The cubic root of 64499661 is about 401.0382631092.

It can be divided in two parts, 6449 and 9661, that added together give a triangular number (16110 = T₁₇₉).

The spelling of 64499661 in words is "sixty-four million, four hundred ninety-nine thousand, six hundred sixty-one".