61621563 has 16 divisors (see below), whose sum is σ = 84875040. Its totient is φ = 39746304.

The previous prime is 61621517. The next prime is 61621589. The reversal of 61621563 is 36512616.

It is not a de Polignac number, because 61621563 - 2¹⁰ = 61620539 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61621563.

It is not an unprimeable number, because it can be changed into a prime (61621663) 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, 8953 + ... + 14261.

It is an arithmetic number, because the mean of its divisors is an integer number (5304690).

Almost surely, 2^61621563 is an apocalyptic number.

61621563 is a deficient number, since it is larger than the sum of its proper divisors (23253477).

61621563 is a wasteful number, since it uses less digits than its factorization.

61621563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5438.

The product of its digits is 6480, while the sum is 30.

The square root of 61621563 is about 7849.9403182445. The cubic root of 61621563 is about 394.9822413637.

The spelling of 61621563 in words is "sixty-one million, six hundred twenty-one thousand, five hundred sixty-three".