70409021 has 4 divisors (see below), whose sum is σ = 70476444. Its totient is φ = 70341600.

The previous prime is 70408993. The next prime is 70409033. The reversal of 70409021 is 12090407.

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 22992025 + 47416996 = 4795^2 + 6886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70409021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70409051) 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, 32120 + ... + 34241.

It is an arithmetic number, because the mean of its divisors is an integer number (17619111).

Almost surely, 2^70409021 is an apocalyptic number.

It is an amenable number.

70409021 is a deficient number, since it is larger than the sum of its proper divisors (67423).

70409021 is a wasteful number, since it uses less digits than its factorization.

70409021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67422.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 70409021 is about 8391.0083422673. The cubic root of 70409021 is about 412.9296821697.

Adding to 70409021 its reverse (12090407), we get a palindrome (82499428).

It can be divided in two parts, 7040 and 9021, that added together give a palindrome (16061).

The spelling of 70409021 in words is "seventy million, four hundred nine thousand, twenty-one".