40209969 has 4 divisors (see below), whose sum is σ = 53613296. Its totient is φ = 26806644.

The previous prime is 40209943. The next prime is 40209989. The reversal of 40209969 is 96990204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 40209969 - 2¹⁵ = 40177201 is a prime.

It is a super-2 number, since 2×40209969² = 3233683213961922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40209989) 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, 6701659 + ... + 6701664.

It is an arithmetic number, because the mean of its divisors is an integer number (13403324).

Almost surely, 2^40209969 is an apocalyptic number.

It is an amenable number.

40209969 is a deficient number, since it is larger than the sum of its proper divisors (13403327).

40209969 is a wasteful number, since it uses less digits than its factorization.

40209969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13403326.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 40209969 is about 6341.1331006375. The cubic root of 40209969 is about 342.5925485597.

The spelling of 40209969 in words is "forty million, two hundred nine thousand, nine hundred sixty-nine".