155172001 has 2 divisors, whose sum is σ = 155172002. Its totient is φ = 155172000.

The previous prime is 155171981. The next prime is 155172023. The reversal of 155172001 is 100271551.

It is an a-pointer prime, because the next prime (155172023) can be obtained adding 155172001 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128142400 + 27029601 = 11320^2 + 5199^2 .

It is a cyclic number.

It is not a de Polignac number, because 155172001 - 2⁷ = 155171873 is a prime.

It is not a weakly prime, because it can be changed into another prime (155172071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77586000 + 77586001.

It is an arithmetic number, because the mean of its divisors is an integer number (77586001).

Almost surely, 2^155172001 is an apocalyptic number.

It is an amenable number.

155172001 is a deficient number, since it is larger than the sum of its proper divisors (1).

155172001 is an equidigital number, since it uses as much as digits as its factorization.

155172001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 350, while the sum is 22.

The square root of 155172001 is about 12456.8054090927. The cubic root of 155172001 is about 537.3671577965.

The spelling of 155172001 in words is "one hundred fifty-five million, one hundred seventy-two thousand, one".