686949401 has 2 divisors, whose sum is σ = 686949402. Its totient is φ = 686949400.

The previous prime is 686949371. The next prime is 686949409. The reversal of 686949401 is 104949686.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 523723225 + 163226176 = 22885^2 + 12776^2 .

It is a cyclic number.

It is not a de Polignac number, because 686949401 - 2⁶ = 686949337 is a prime.

It is not a weakly prime, because it can be changed into another prime (686949409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343474700 + 343474701.

It is an arithmetic number, because the mean of its divisors is an integer number (343474701).

Almost surely, 2^686949401 is an apocalyptic number.

It is an amenable number.

686949401 is a deficient number, since it is larger than the sum of its proper divisors (1).

686949401 is an equidigital number, since it uses as much as digits as its factorization.

686949401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 373248, while the sum is 47.

The square root of 686949401 is about 26209.7195902589. The cubic root of 686949401 is about 882.3514080246.

The spelling of 686949401 in words is "six hundred eighty-six million, nine hundred forty-nine thousand, four hundred one".