1465020721 has 4 divisors (see below), whose sum is σ = 1485089572. Its totient is φ = 1444951872.

The previous prime is 1465020701. The next prime is 1465020731. The reversal of 1465020721 is 1270205641.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 263705121 + 1201315600 = 16239^2 + 34660^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1465020721 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1465020721.

It is not an unprimeable number, because it can be changed into a prime (1465020701) 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, 10034316 + ... + 10034461.

It is an arithmetic number, because the mean of its divisors is an integer number (371272393).

Almost surely, 2^1465020721 is an apocalyptic number.

It is an amenable number.

1465020721 is a deficient number, since it is larger than the sum of its proper divisors (20068851).

1465020721 is an equidigital number, since it uses as much as digits as its factorization.

1465020721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20068850.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 1465020721 is about 38275.5891006265. The cubic root of 1465020721 is about 1135.7461041662.

The spelling of 1465020721 in words is "one billion, four hundred sixty-five million, twenty thousand, seven hundred twenty-one".