145467721 has 9 divisors (see below), whose sum is σ = 169315821. Its totient is φ = 124614252.

The previous prime is 145467671. The next prime is 145467731. The reversal of 145467721 is 127764541.

The square root of 145467721 is 12061.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 145467721 - 2¹³ = 145459529 is a prime.

It is a super-4 number, since 4×145467721⁴ (a number of 34 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145467731) 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 8 ways as a sum of consecutive naturals, for example, 83566 + ... + 85288.

It is an arithmetic number, because the mean of its divisors is an integer number (18812869).

Almost surely, 2^145467721 is an apocalyptic number.

145467721 is the 12061-st square number.

145467721 is the 6031-st centered octagonal number.

It is an amenable number.

145467721 is a deficient number, since it is larger than the sum of its proper divisors (23848100).

145467721 is an frugal number, since it uses more digits than its factorization.

145467721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3460 (or 1730 counting only the distinct ones).

The product of its digits is 47040, while the sum is 37.

The cubic root of 145467721 is about 525.9230576059.

The spelling of 145467721 in words is "one hundred forty-five million, four hundred sixty-seven thousand, seven hundred twenty-one".