64778101 has 2 divisors, whose sum is σ = 64778102. Its totient is φ = 64778100.

The previous prime is 64778089. The next prime is 64778111. The reversal of 64778101 is 10187746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43164900 + 21613201 = 6570^2 + 4649^2 .

It is a cyclic number.

It is not a de Polignac number, because 64778101 - 2²¹ = 62680949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64778111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32389050 + 32389051.

It is an arithmetic number, because the mean of its divisors is an integer number (32389051).

Almost surely, 2^64778101 is an apocalyptic number.

It is an amenable number.

64778101 is a deficient number, since it is larger than the sum of its proper divisors (1).

64778101 is an equidigital number, since it uses as much as digits as its factorization.

64778101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9408, while the sum is 34.

The square root of 64778101 is about 8048.4843914864. The cubic root of 64778101 is about 401.6145183088.

The spelling of 64778101 in words is "sixty-four million, seven hundred seventy-eight thousand, one hundred one".