129870981 has 6 divisors (see below), whose sum is σ = 187591430. Its totient is φ = 86580648.

The previous prime is 129870971. The next prime is 129871031. The reversal of 129870981 is 189078921.

It can be written as a sum of positive squares in only one way, i.e., 106193025 + 23677956 = 10305^2 + 4866^2 .

It is not a de Polignac number, because 129870981 - 2⁹ = 129870469 is a prime.

It is a super-2 number, since 2×129870981² = 33732943411804722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129870971) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7215046 + ... + 7215063.

Almost surely, 2^129870981 is an apocalyptic number.

It is an amenable number.

129870981 is a deficient number, since it is larger than the sum of its proper divisors (57720449).

129870981 is a wasteful number, since it uses less digits than its factorization.

129870981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14430115 (or 14430112 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 129870981 is about 11396.0949890741. The cubic root of 129870981 is about 506.4120607813.

The spelling of 129870981 in words is "one hundred twenty-nine million, eight hundred seventy thousand, nine hundred eighty-one".