20513070 has 48 divisors (see below), whose sum is σ = 53576640. Its totient is φ = 5445312.

The previous prime is 20513069. The next prime is 20513071. The reversal of 20513070 is 7031502.

It is an interprime number because it is at equal distance from previous prime (20513069) and next prime (20513071).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20513071) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28171 + ... + 28889.

It is an arithmetic number, because the mean of its divisors is an integer number (1116180).

Almost surely, 2^20513070 is an apocalyptic number.

20513070 is an abundant number, since it is smaller than the sum of its proper divisors (33063570).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20513070 is a wasteful number, since it uses less digits than its factorization.

20513070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1049 (or 1046 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 20513070 is about 4529.1356791335. The cubic root of 20513070 is about 273.7433350476.

Adding to 20513070 its reverse (7031502), we get a palindrome (27544572).

The spelling of 20513070 in words is "twenty million, five hundred thirteen thousand, seventy".