145721900 has 18 divisors (see below), whose sum is σ = 316216740. Its totient is φ = 58288720.

The previous prime is 145721893. The next prime is 145721903. The reversal of 145721900 is 9127541.

It is a super-2 number, since 2×145721900² = 42469744279220000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (145721903) 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 5 ways as a sum of consecutive naturals, for example, 728510 + ... + 728709.

Almost surely, 2^145721900 is an apocalyptic number.

145721900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

145721900 is an abundant number, since it is smaller than the sum of its proper divisors (170494840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

145721900 is a wasteful number, since it uses less digits than its factorization.

145721900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1457233 (or 1457226 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 145721900 is about 12071.5326284611. The cubic root of 145721900 is about 526.2291984037.

The spelling of 145721900 in words is "one hundred forty-five million, seven hundred twenty-one thousand, nine hundred".