998156777 has 2 divisors, whose sum is σ = 998156778. Its totient is φ = 998156776.

The previous prime is 998156723. The next prime is 998156801. The reversal of 998156777 is 777651899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 875035561 + 123121216 = 29581^2 + 11096^2 .

It is a cyclic number.

It is not a de Polignac number, because 998156777 - 2¹² = 998152681 is a prime.

It is not a weakly prime, because it can be changed into another prime (998156177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499078388 + 499078389.

It is an arithmetic number, because the mean of its divisors is an integer number (499078389).

Almost surely, 2^998156777 is an apocalyptic number.

It is an amenable number.

998156777 is a deficient number, since it is larger than the sum of its proper divisors (1).

998156777 is an equidigital number, since it uses as much as digits as its factorization.

998156777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6667920, while the sum is 59.

The square root of 998156777 is about 31593.6192450311. The cubic root of 998156777 is about 999.3852144495.

The spelling of 998156777 in words is "nine hundred ninety-eight million, one hundred fifty-six thousand, seven hundred seventy-seven".