40721961 has 8 divisors (see below), whose sum is σ = 62052544. Its totient is φ = 23269680.

The previous prime is 40721929. The next prime is 40721969. The reversal of 40721961 is 16912704.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 40721961 - 2⁵ = 40721929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40721969) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 969550 + ... + 969591.

It is an arithmetic number, because the mean of its divisors is an integer number (7756568).

Almost surely, 2^40721961 is an apocalyptic number.

It is an amenable number.

40721961 is a deficient number, since it is larger than the sum of its proper divisors (21330583).

40721961 is a wasteful number, since it uses less digits than its factorization.

40721961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1939151.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 40721961 is about 6381.3761055120. The cubic root of 40721961 is about 344.0404929122.

The spelling of 40721961 in words is "forty million, seven hundred twenty-one thousand, nine hundred sixty-one".