151721651 has 4 divisors (see below), whose sum is σ = 160646472. Its totient is φ = 142796832.

The previous prime is 151721623. The next prime is 151721681. The reversal of 151721651 is 156127151.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 156127151 = 23 ⋅6788137.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-151721651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (151721681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4462385 + ... + 4462418.

It is an arithmetic number, because the mean of its divisors is an integer number (40161618).

Almost surely, 2^151721651 is an apocalyptic number.

151721651 is a deficient number, since it is larger than the sum of its proper divisors (8924821).

151721651 is an equidigital number, since it uses as much as digits as its factorization.

151721651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8924820.

The product of its digits is 2100, while the sum is 29.

The square root of 151721651 is about 12317.5342905957. The cubic root of 151721651 is about 533.3543644918.

The spelling of 151721651 in words is "one hundred fifty-one million, seven hundred twenty-one thousand, six hundred fifty-one".