40829721 has 16 divisors (see below), whose sum is σ = 55238400. Its totient is φ = 26823888.

The previous prime is 40829717. The next prime is 40829741. The reversal of 40829721 is 12792804.

It is a happy number.

It is not a de Polignac number, because 40829721 - 2² = 40829717 is a prime.

It is a super-3 number, since 3×40829721³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (40829741) 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, 74370 + ... + 74916.

It is an arithmetic number, because the mean of its divisors is an integer number (3452400).

Almost surely, 2^40829721 is an apocalyptic number.

It is an amenable number.

40829721 is a deficient number, since it is larger than the sum of its proper divisors (14408679).

40829721 is a wasteful number, since it uses less digits than its factorization.

40829721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 868.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 40829721 is about 6389.8138470538. The cubic root of 40829721 is about 344.3436966264.

The spelling of 40829721 in words is "forty million, eight hundred twenty-nine thousand, seven hundred twenty-one".