155642129 has 4 divisors (see below), whose sum is σ = 163833840. Its totient is φ = 147450420.

The previous prime is 155642117. The next prime is 155642141. The reversal of 155642129 is 921246551.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (155642117) and next prime (155642141).

It is a cyclic number.

It is not a de Polignac number, because 155642129 - 2¹⁶ = 155576593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155642189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4095827 + ... + 4095864.

It is an arithmetic number, because the mean of its divisors is an integer number (40958460).

Almost surely, 2^155642129 is an apocalyptic number.

155642129 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

155642129 is a deficient number, since it is larger than the sum of its proper divisors (8191711).

155642129 is an equidigital number, since it uses as much as digits as its factorization.

155642129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8191710.

The product of its digits is 21600, while the sum is 35.

The square root of 155642129 is about 12475.6614654294. The cubic root of 155642129 is about 537.9093016538.

The spelling of 155642129 in words is "one hundred fifty-five million, six hundred forty-two thousand, one hundred twenty-nine".