64780091 has 2 divisors, whose sum is σ = 64780092. Its totient is φ = 64780090.

The previous prime is 64780073. The next prime is 64780097. The reversal of 64780091 is 19008746.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64780091 - 2¹⁰ = 64779067 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (64780097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32390045 + 32390046.

It is an arithmetic number, because the mean of its divisors is an integer number (32390046).

Almost surely, 2^64780091 is an apocalyptic number.

64780091 is a deficient number, since it is larger than the sum of its proper divisors (1).

64780091 is an equidigital number, since it uses as much as digits as its factorization.

64780091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 64780091 is about 8048.6080162970. The cubic root of 64780091 is about 401.6186308340.

The spelling of 64780091 in words is "sixty-four million, seven hundred eighty thousand, ninety-one".