20870129 has 12 divisors (see below), whose sum is σ = 24692400. Its totient is φ = 17583048.

The previous prime is 20870119. The next prime is 20870137. The reversal of 20870129 is 92107802.

It is a happy number.

It is not a de Polignac number, because 20870129 - 2⁸ = 20869873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20870119) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 719 + ... + 6500.

It is an arithmetic number, because the mean of its divisors is an integer number (2057700).

Almost surely, 2^20870129 is an apocalyptic number.

It is an amenable number.

20870129 is a deficient number, since it is larger than the sum of its proper divisors (3822271).

20870129 is an equidigital number, since it uses as much as digits as its factorization.

20870129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7292 (or 7285 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 20870129 is about 4568.3836310012. The cubic root of 20870129 is about 275.3225042822.

The spelling of 20870129 in words is "twenty million, eight hundred seventy thousand, one hundred twenty-nine".