40720261 has 4 divisors (see below), whose sum is σ = 40859532. Its totient is φ = 40580992.

The previous prime is 40720247. The next prime is 40720279. The reversal of 40720261 is 16202704.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16769025 + 23951236 = 4095^2 + 4894^2 .

It is a cyclic number.

It is not a de Polignac number, because 40720261 - 2¹³ = 40712069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40720201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69196 + ... + 69781.

It is an arithmetic number, because the mean of its divisors is an integer number (10214883).

Almost surely, 2^40720261 is an apocalyptic number.

It is an amenable number.

40720261 is a deficient number, since it is larger than the sum of its proper divisors (139271).

40720261 is a wasteful number, since it uses less digits than its factorization.

40720261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139270.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 40720261 is about 6381.2429040117. The cubic root of 40720261 is about 344.0357053483.

Adding to 40720261 its reverse (16202704), we get a palindrome (56922965).

The spelling of 40720261 in words is "forty million, seven hundred twenty thousand, two hundred sixty-one".