697906561 has 16 divisors (see below), whose sum is σ = 775228608. Its totient is φ = 623001600.

The previous prime is 697906541. The next prime is 697906577. The reversal of 697906561 is 165609796.

It is a 2-Lehmer number, since φ(697906561) divides (697906561-1)².

It is a cyclic number.

It is a Carmichael number.

It is not a de Polignac number, because 697906561 - 2¹¹ = 697904513 is a prime.

It is a deceptive number, since it divides R_697906560.

It is not an unprimeable number, because it can be changed into a prime (697906511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137281 + ... + 142273.

It is an arithmetic number, because the mean of its divisors is an integer number (48451788).

It is a Poulet number, since it divides 2^697906560-1.

Almost surely, 2^697906561 is an apocalyptic number.

It is an amenable number.

697906561 is a deficient number, since it is larger than the sum of its proper divisors (77322047).

697906561 is a wasteful number, since it uses less digits than its factorization.

697906561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5232.

The product of its (nonzero) digits is 612360, while the sum is 49.

The square root of 697906561 is about 26417.9212089067. The cubic root of 697906561 is about 887.0179879732.

The spelling of 697906561 in words is "six hundred ninety-seven million, nine hundred six thousand, five hundred sixty-one".