221754540 has 48 divisors (see below), whose sum is σ = 709615872. Its totient is φ = 50686656.

The previous prime is 221754539. The next prime is 221754541. The reversal of 221754540 is 45457122.

It is an interprime number because it is at equal distance from previous prime (221754539) and next prime (221754541).

It is a super-2 number, since 2×221754540² = 98350152021223200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 221754498 and 221754507.

It is not an unprimeable number, because it can be changed into a prime (221754541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 263574 + ... + 264413.

It is an arithmetic number, because the mean of its divisors is an integer number (14783664).

Almost surely, 2^221754540 is an apocalyptic number.

221754540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221754540 is an abundant number, since it is smaller than the sum of its proper divisors (487861332).

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

221754540 is a wasteful number, since it uses less digits than its factorization.

221754540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528006 (or 528004 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 30.

The square root of 221754540 is about 14891.4250493363. The cubic root of 221754540 is about 605.2816483404.

The spelling of 221754540 in words is "two hundred twenty-one million, seven hundred fifty-four thousand, five hundred forty".