611561387 has 2 divisors, whose sum is σ = 611561388. Its totient is φ = 611561386.

The previous prime is 611561333. The next prime is 611561399. The reversal of 611561387 is 783165116.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 611561387 - 2⁶ = 611561323 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 611561387.

It is not a weakly prime, because it can be changed into another prime (611561887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305780693 + 305780694.

It is an arithmetic number, because the mean of its divisors is an integer number (305780694).

Almost surely, 2^611561387 is an apocalyptic number.

611561387 is a deficient number, since it is larger than the sum of its proper divisors (1).

611561387 is an equidigital number, since it uses as much as digits as its factorization.

611561387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 38.

The square root of 611561387 is about 24729.7672249457. The cubic root of 611561387 is about 848.8155993120.

The spelling of 611561387 in words is "six hundred eleven million, five hundred sixty-one thousand, three hundred eighty-seven".