64490621 has 8 divisors (see below), whose sum is σ = 70140504. Its totient is φ = 58939200.

The previous prime is 64490563. The next prime is 64490641. The reversal of 64490621 is 12609446.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 28622500 + 35868121 = 5350^2 + 5989^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64490621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64490641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23246 + ... + 25871.

It is an arithmetic number, because the mean of its divisors is an integer number (8767563).

Almost surely, 2^64490621 is an apocalyptic number.

It is an amenable number.

64490621 is a deficient number, since it is larger than the sum of its proper divisors (5649883).

64490621 is a wasteful number, since it uses less digits than its factorization.

64490621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49231.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 64490621 is about 8030.6052698411. The cubic root of 64490621 is about 401.0195262909.

The spelling of 64490621 in words is "sixty-four million, four hundred ninety thousand, six hundred twenty-one".