987977251 has 2 divisors, whose sum is σ = 987977252. Its totient is φ = 987977250.

The previous prime is 987977233. The next prime is 987977273. The reversal of 987977251 is 152779789.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-987977251 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 987977192 and 987977201.

It is not a weakly prime, because it can be changed into another prime (987977201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 493988625 + 493988626.

It is an arithmetic number, because the mean of its divisors is an integer number (493988626).

Almost surely, 2^987977251 is an apocalyptic number.

987977251 is a deficient number, since it is larger than the sum of its proper divisors (1).

987977251 is an equidigital number, since it uses as much as digits as its factorization.

987977251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2222640, while the sum is 55.

The square root of 987977251 is about 31432.1054178685. The cubic root of 987977251 is about 995.9762481366.

The spelling of 987977251 in words is "nine hundred eighty-seven million, nine hundred seventy-seven thousand, two hundred fifty-one".