70138821 has 16 divisors (see below), whose sum is σ = 99952704. Its totient is φ = 43593984.

The previous prime is 70138819. The next prime is 70138843. The reversal of 70138821 is 12883107.

It is a happy number.

It is not a de Polignac number, because 70138821 - 2¹ = 70138819 is a prime.

It is a super-2 number, since 2×70138821² = 9838908422540082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70138811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 970 + ... + 11883.

It is an arithmetic number, because the mean of its divisors is an integer number (6247044).

Almost surely, 2^70138821 is an apocalyptic number.

It is an amenable number.

70138821 is a deficient number, since it is larger than the sum of its proper divisors (29813883).

70138821 is a wasteful number, since it uses less digits than its factorization.

70138821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12980.

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 70138821 is about 8374.8922978149. The cubic root of 70138821 is about 412.4007886289.

The spelling of 70138821 in words is "seventy million, one hundred thirty-eight thousand, eight hundred twenty-one".