151551221 has 8 divisors (see below), whose sum is σ = 158004000. Its totient is φ = 145231632.

The previous prime is 151551203. The next prime is 151551229. The reversal of 151551221 is 122155151.

151551221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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-151551221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (151551229) 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, 30971 + ... + 35528.

It is an arithmetic number, because the mean of its divisors is an integer number (19750500).

Almost surely, 2^151551221 is an apocalyptic number.

It is an amenable number.

151551221 is a deficient number, since it is larger than the sum of its proper divisors (6452779).

151551221 is an equidigital number, since it uses as much as digits as its factorization.

151551221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66595.

The product of its digits is 500, while the sum is 23.

The square root of 151551221 is about 12310.6141601465. The cubic root of 151551221 is about 533.1545827621.

The spelling of 151551221 in words is "one hundred fifty-one million, five hundred fifty-one thousand, two hundred twenty-one".