20155251 has 8 divisors (see below), whose sum is σ = 28454544. Its totient is φ = 12646400.

The previous prime is 20155249. The next prime is 20155271. The reversal of 20155251 is 15255102.

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

It is a cyclic number.

It is not a de Polignac number, because 20155251 - 2¹ = 20155249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20155271) 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, 197550 + ... + 197651.

It is an arithmetic number, because the mean of its divisors is an integer number (3556818).

Almost surely, 2^20155251 is an apocalyptic number.

20155251 is a deficient number, since it is larger than the sum of its proper divisors (8299293).

20155251 is a wasteful number, since it uses less digits than its factorization.

20155251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395221.

The product of its (nonzero) digits is 500, while the sum is 21.

The square root of 20155251 is about 4489.4599897983. The cubic root of 20155251 is about 272.1423121705.

The spelling of 20155251 in words is "twenty million, one hundred fifty-five thousand, two hundred fifty-one".