151120721 has 4 divisors (see below), whose sum is σ = 151239792. Its totient is φ = 151001652.

The previous prime is 151120709. The next prime is 151120747. The reversal of 151120721 is 127021151.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 151120721 - 2⁶ = 151120657 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 151120693 and 151120702.

It is not an unprimeable number, because it can be changed into a prime (151120751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57611 + ... + 60176.

It is an arithmetic number, because the mean of its divisors is an integer number (37809948).

Almost surely, 2^151120721 is an apocalyptic number.

It is an amenable number.

151120721 is a deficient number, since it is larger than the sum of its proper divisors (119071).

151120721 is a wasteful number, since it uses less digits than its factorization.

151120721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119070.

The product of its (nonzero) digits is 140, while the sum is 20.

The square root of 151120721 is about 12293.1168138922. The cubic root of 151120721 is about 532.6492734690.

Adding to 151120721 its reverse (127021151), we get a palindrome (278141872).

The spelling of 151120721 in words is "one hundred fifty-one million, one hundred twenty thousand, seven hundred twenty-one".