64778453 has 4 divisors (see below), whose sum is σ = 66529260. Its totient is φ = 63027648.

The previous prime is 64778447. The next prime is 64778459. The reversal of 64778453 is 35487746.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (64778447) and next prime (64778459).

It can be written as a sum of positive squares in 2 ways, for example, as 51868804 + 12909649 = 7202^2 + 3593^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64778453 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 (64778459) 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, 875348 + ... + 875421.

It is an arithmetic number, because the mean of its divisors is an integer number (16632315).

Almost surely, 2^64778453 is an apocalyptic number.

It is an amenable number.

64778453 is a deficient number, since it is larger than the sum of its proper divisors (1750807).

64778453 is a wasteful number, since it uses less digits than its factorization.

64778453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1750806.

The product of its digits is 564480, while the sum is 44.

The square root of 64778453 is about 8048.5062589278. The cubic root of 64778453 is about 401.6152457566.

The spelling of 64778453 in words is "sixty-four million, seven hundred seventy-eight thousand, four hundred fifty-three".