172026421 has 8 divisors (see below), whose sum is σ = 196680960. Its totient is φ = 147391728.

The previous prime is 172026391. The next prime is 172026427. The reversal of 172026421 is 124620271.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172026421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172026427) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31620 + ... + 36658.

It is an arithmetic number, because the mean of its divisors is an integer number (24585120).

Almost surely, 2^172026421 is an apocalyptic number.

It is an amenable number.

172026421 is a deficient number, since it is larger than the sum of its proper divisors (24654539).

172026421 is an equidigital number, since it uses as much as digits as its factorization.

172026421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9923.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 172026421 is about 13115.8843011060. The cubic root of 172026421 is about 556.1582509787.

Adding to 172026421 its reverse (124620271), we get a palindrome (296646692).

The spelling of 172026421 in words is "one hundred seventy-two million, twenty-six thousand, four hundred twenty-one".