128902861 has 2 divisors, whose sum is σ = 128902862. Its totient is φ = 128902860.

The previous prime is 128902759. The next prime is 128902871. The reversal of 128902861 is 168209821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79762761 + 49140100 = 8931^2 + 7010^2 .

It is a cyclic number.

It is not a de Polignac number, because 128902861 - 2²¹ = 126805709 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128902861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128902871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64451430 + 64451431.

It is an arithmetic number, because the mean of its divisors is an integer number (64451431).

Almost surely, 2^128902861 is an apocalyptic number.

It is an amenable number.

128902861 is a deficient number, since it is larger than the sum of its proper divisors (1).

128902861 is an equidigital number, since it uses as much as digits as its factorization.

128902861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 128902861 is about 11353.5395802366. The cubic root of 128902861 is about 505.1505756259.

It can be divided in two parts, 12890 and 2861, that added together give a palindrome (15751).

The spelling of 128902861 in words is "one hundred twenty-eight million, nine hundred two thousand, eight hundred sixty-one".