40399742721 has 32 divisors (see below), whose sum is σ = 59036479488. Its totient is φ = 24425164800.

The previous prime is 40399742699. The next prime is 40399742783. The reversal of 40399742721 is 12724799304.

It is a happy number.

It is not a de Polignac number, because 40399742721 - 2¹⁸ = 40399480577 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40399722721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 479296 + ... + 557246.

It is an arithmetic number, because the mean of its divisors is an integer number (1844889984).

Almost surely, 2^40399742721 is an apocalyptic number.

It is an amenable number.

40399742721 is a deficient number, since it is larger than the sum of its proper divisors (18636736767).

40399742721 is a wasteful number, since it uses less digits than its factorization.

40399742721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78201.

The product of its (nonzero) digits is 762048, while the sum is 48.

The spelling of 40399742721 in words is "forty billion, three hundred ninety-nine million, seven hundred forty-two thousand, seven hundred twenty-one".