651549091 has 2 divisors, whose sum is σ = 651549092. Its totient is φ = 651549090.

The previous prime is 651549053. The next prime is 651549131. The reversal of 651549091 is 190945156.

It is an a-pointer prime, because the next prime (651549131) can be obtained adding 651549091 to its sum of digits (40).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 651549091 - 2¹⁵ = 651516323 is a prime.

It is not a weakly prime, because it can be changed into another prime (651549011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 325774545 + 325774546.

It is an arithmetic number, because the mean of its divisors is an integer number (325774546).

Almost surely, 2^651549091 is an apocalyptic number.

651549091 is a deficient number, since it is larger than the sum of its proper divisors (1).

651549091 is an equidigital number, since it uses as much as digits as its factorization.

651549091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48600, while the sum is 40.

The square root of 651549091 is about 25525.4596628543. The cubic root of 651549091 is about 866.9267046289.

The spelling of 651549091 in words is "six hundred fifty-one million, five hundred forty-nine thousand, ninety-one".