261622679 has 2 divisors, whose sum is σ = 261622680. Its totient is φ = 261622678.

The previous prime is 261622657. The next prime is 261622687. The reversal of 261622679 is 976226162.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261622679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261622619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130811339 + 130811340.

It is an arithmetic number, because the mean of its divisors is an integer number (130811340).

Almost surely, 2^261622679 is an apocalyptic number.

261622679 is a deficient number, since it is larger than the sum of its proper divisors (1).

261622679 is an equidigital number, since it uses as much as digits as its factorization.

261622679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 261622679 is about 16174.7543721690. The cubic root of 261622679 is about 639.5754663388.

The spelling of 261622679 in words is "two hundred sixty-one million, six hundred twenty-two thousand, six hundred seventy-nine".