987356921 has 2 divisors, whose sum is σ = 987356922. Its totient is φ = 987356920.

The previous prime is 987356879. The next prime is 987356941. The reversal of 987356921 is 129653789.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 960690025 + 26666896 = 30995^2 + 5164^2 .

It is a cyclic number.

It is not a de Polignac number, because 987356921 - 2²² = 983162617 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 987356921.

It is not a weakly prime, because it can be changed into another prime (987356941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493678460 + 493678461.

It is an arithmetic number, because the mean of its divisors is an integer number (493678461).

Almost surely, 2^987356921 is an apocalyptic number.

It is an amenable number.

987356921 is a deficient number, since it is larger than the sum of its proper divisors (1).

987356921 is an equidigital number, since it uses as much as digits as its factorization.

987356921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 50.

The square root of 987356921 is about 31422.2360916597. The cubic root of 987356921 is about 995.7677536937.

The spelling of 987356921 in words is "nine hundred eighty-seven million, three hundred fifty-six thousand, nine hundred twenty-one".