65428991 has 2 divisors, whose sum is σ = 65428992. Its totient is φ = 65428990.

The previous prime is 65428981. The next prime is 65429009. The reversal of 65428991 is 19982456.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65428991 - 2⁶ = 65428927 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65428981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32714495 + 32714496.

It is an arithmetic number, because the mean of its divisors is an integer number (32714496).

Almost surely, 2^65428991 is an apocalyptic number.

65428991 is a deficient number, since it is larger than the sum of its proper divisors (1).

65428991 is an equidigital number, since it uses as much as digits as its factorization.

65428991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 44.

The square root of 65428991 is about 8088.8188878229. The cubic root of 65428991 is about 402.9551781227.

The spelling of 65428991 in words is "sixty-five million, four hundred twenty-eight thousand, nine hundred ninety-one".