145721725 has 24 divisors (see below), whose sum is σ = 186595200. Its totient is φ = 112806720.

The previous prime is 145721701. The next prime is 145721729. The reversal of 145721725 is 527127541.

It is not a de Polignac number, because 145721725 - 2¹⁵ = 145688957 is a prime.

It is a super-2 number, since 2×145721725² = 42469642273951250, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145721729) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 242976 + ... + 243574.

It is an arithmetic number, because the mean of its divisors is an integer number (7774800).

Almost surely, 2^145721725 is an apocalyptic number.

It is an amenable number.

145721725 is a deficient number, since it is larger than the sum of its proper divisors (40873475).

145721725 is a wasteful number, since it uses less digits than its factorization.

145721725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 909 (or 904 counting only the distinct ones).

The product of its digits is 19600, while the sum is 34.

The square root of 145721725 is about 12071.5253800007. The cubic root of 145721725 is about 526.2289877510.

The spelling of 145721725 in words is "one hundred forty-five million, seven hundred twenty-one thousand, seven hundred twenty-five".